Transformers Low Voltage

Transcription

1 00Dstrbuton Dry-Type Aprl 0 Sheet Dstrbuton Dry-Type TransformersLow Voltage.0- TransformersLow Voltage Contents Dstrbuton Dry-Type TransformersLow Voltage Glossary of Transformer Terms The Energy Polcy Act of General Descrpton/Product Overvew Ventlated General Purpose Encapsulated K-Factor Rated for Nonlnear Loads (KT Type) Harmonc Mtgatng (HMT Type) Motor Drve Isolaton Hazardous Locaton Mn Power Centers FAQ Specfcatons See Eaton s Product Specfcaton Gude, avalable on CD or on the Web. CSI Format: Dry-Type Transformers Mn Power Centers Further Informaton Volume Commercal Dstrbuton 0, Tab CA00000E Eaton s Famly of Dry-Type Dstrbuton Transformers 0 0 CA0000E For more nformaton, vst:

2 .0- Dstrbuton Dry-Type TransformersLow Voltage Glossary Aprl 0 Sheet Glossary of Transformer Terms Ar cooled: A transformer that s cooled by the natural crculaton of ar around, or through, the core and cols. Ambent nose level: The exstng or nherent sound level of the area surroundng the transformer, pror to energzng the transformer. Measured n decbels. Ambent temperature: The temperature of the ar surroundng the transformer nto whch the heat of the transformer s dsspated. Ampacty: The current-carryng capacty of an electrcal conductor under stated thermal condtons. Expressed n amperes. Ampere: The practcal unt of electrc current. Attenuaton: A decrease n sgnal power or voltage. Unt of measure s db. Autotransformer: A transformer n whch part of the wndng s common to both the prmary and the secondary crcuts. Banked: Two or more sngle-phase transformers wred together to supply a three-phase load. Three sngle-phase transformers can be banked together to support a three-phase load. For example, three 0 kva sngle-phase transformers banked together wll have a 0 kva three-phase capacty. BIL: Basc mpulse level. The ablty of a transformer s nsulaton system to wthstand hgh voltage surges. All Eaton 00 V-class transformers have a 0 kv BIL ratng. BTU: Brtsh thermal unt. In North Amerca, the term BTU s used to descrbe the heat value (energy content) of fuels, and also to descrbe the power of heatng and coolng systems, such as furnaces, stoves, barbecue grlls and ar condtoners. When used as a unt of power, BTU per hour (BTU/h) s understood, though ths s often abbrevated to just BTU. Buck-boost: The name of a standard, sngle-phase, two-wndng transformer applcaton wth the low voltage secondary wndngs connected as an autotransformer for boostng (ncreasng) or buckng (decreasng) voltages n small amounts. Applcatons can ether be sngle-phase or three-phase. CE: Mark to ndcate thrd-party approved or self-certfcaton to specfc requrements of the European communty. Celsus (centgrade): Metrc temperature measure. F = (. x C) + C = ( F-) /. Center tap: A reduced capacty tap at the md-pont of a wndng. The center tap on three-phase delta-delta transformers s called a lghtng tap. It provdes % of the transformer s kva for sngle-phase loads. Certfed tests: Actual values taken durng producton tests and certfed as applyng to a gven unt shpped on a specfc order. Certfed tests are seral number specfc. Common mode: Electrcal nose or voltage fluctuaton that occurs between all of the lne leads and the common ground, or between ground and lne or neutral. Compensated transformer: A transformer wth a turns rato that provdes a hgher than nameplate output (secondary) voltage at no load, and nameplate output (secondary) voltage at rated load. It s common for small transformers ( kva and less) to be compensated. Conductor losses: Losses (expressed n watts) n a transformer that are ncdental to carryng a load: col resstance, stray loss due to stray fluxes n the wndngs, core clamps, and the lke, as well as crculatng currents (f any) n parallel wndngs. Also called load losses. Contnuous duty ratng: The load that a transformer can handle ndefntely wthout exceedng ts specfed temperature rse. Core losses: Losses (expressed n watts) caused by magnetzaton of the core and ts resstance to magnetc flux. Also called no-load losses or exctaton losses. Core losses are always present when the transformer s energzed. CSA: Canadan Standards Assocaton. The Canadan equvalent of Underwrters Laboratores (UL). CSL: Canddate Standard Level (CSL) desgn crtera developed by the U.S. Department of Energy. cul: Mark to ndcate UL Certfcaton to specfc CSA Standards. Decbel (db): Unt of measure used to express the magntude of a change n sgnal or sound level. Delta connecton: A standard threephase connecton wth the ends of each phase wndng connected n seres to form a closed loop wth each phase 0 degrees from the other. Sometmes referred to as three-wre. Delectrc tests: Tests that consst of the applcaton of a voltage hgher than the rated voltage for a specfed tme for the purpose of determnng the adequacy aganst breakdowns of nsulatng materals and spacngs under normal condtons. DOE 0 effcent: A revson to federal law 0 CFR Part (00) that mandates hgher effcency for dstrbuton transformers manufactured for sale n the U.S. and U.S. Terrtores effectve January, 0. TP- effcent transformers can no longer legally be manufactured for use n the U.S. as of ths date. Dry-type transformer: A transformer n whch the core and cols are n a gaseous or dry compound nsulatng medum. A transformer that s cooled by a medum other than a lqud, normally by the crculaton of ar. E: Eaton s verson of a CSL transformer. Eddy currents: The currents that are nduced n the body of a conductng mass by the tme varaton of magnetc flux or varyng magnetc feld. Effcency: The rato of the power output from a transformer to the total power nput. Typcally expressed as a %. Electrostatc sheld: Copper or other conductng sheet placed between prmary and secondary wndngs, and grounded to reduce electrcal nterference and to provde addtonal protecton from lne-to-lne or lne-toground nose. Commonly referred to as Faraday sheld. Encapsulated transformer: A transformer wth ts cols ether dpped or cast n an epoxy resn or other encapsulatng substance. For more nformaton, vst: CA0000E

3 Aprl 0 Sheet 00 Dstrbuton Dry-Type TransformersLow Voltage Glossary.0- Enclosure: A surroundng case or housng used to protect the contaned equpment aganst external condtons and prevent personnel from accdentally contactng lve parts. Envronmentally preferable product: A product that has a lesser or reduced negatve effect on human health and the envronment when compared to competng products that serve the same purpose. Ths comparson may consder raw materals acquston, producton, manufacturng, packagng, dstrbuton, reuse, operaton, mantenance and dsposal of the product. Ths term ncludes recyclable products, recycled products and reusable products. EPACT: The Energy Polcy Act of (EPAct) s an mportant pece of legslaton for effcency because t establshed mnmum effcency levels for dry-type dstrbuton transformers manufactured or mported after December 00. EPAct, whch was based on NEMA standards, defned a number of terms, ncludng what consttutes an energy-effcent transformer. The DOE ssued a rule that defnes these transformers and how manufacturers must comply. In Aprl 0, the DOE mandated even hgher mnmum effcency levels for dstrbuton transformers effectve startng n January 0. DOE EPAct rule (PDF): Energy Effcency Program for Certan Commercal and Industral Equpment: Test Procedures, Labelng, and the Certfcaton Requrements for Electrc Motors. Fnal Rule. 0-CFR Part. Exctaton current: No load current. The current that flows n any wndng used to excte the transformer when all other wndngs are open-crcuted. It s usually expressed n percent of the rated current of a wndng n whch t s measured. Also called magnetzng current. FCAN: Full Capacty Above Nomnal taps. Desgnates the transformer wll delver ts rated kva when connected to a voltage source whch s hgher than the rated prmary voltage. FCBN: Full Capacty Below Nomnal taps. Desgnates the transformer wll delver ts rated kva when connected to a voltage source whch s lower than the rated prmary voltage. Frequency: On AC crcuts, desgnates the number of tmes that polarty alternates from postve to negatve and back agan per second, such as 0 cycles per second. Typcally measured n Hertz (Hz). Ground: Connectng one sde of a crcut to the earth through low resstance or low mpedance paths to help prevent transmttng electrcal shock to personnel. Harmonc: A snusodal waveform wth a frequency that s an ntegral multple of the fundamental frequency (0 Hz). 0 H fundamental 0 H nd harmonc 0 H rd harmonc 0 H th harmonc Harmonc dstorton: Nonlnear dstorton of a system characterzed by the appearance of harmonc (non-snusodal) currents n the output, when the nput s snusodal. Harmonc dstorton, total (THD): The square root of the sum of the squares of all harmonc currents present n a load, excludng the fundamental 0 Hz current. Usually expressed as a percent of the fundamental. Hgh voltage wndngs: In a twowndng transformer, the wndng ntended to have the greater voltage. Usually marked wth H desgnatons. HMT: Harmonc Mtgatng Transformer (HMT) s better able to handle the harmonc currents present n today s electrcal power system. thereby ncreasng system capacty, reducng dstorton throughout a faclty, help to mnmze downtme and mysterous mantenance on equpment, and return the longevty of equpment lfe through reduced operatonal energy losses, thereby runnng cooler. Hp: Horsepower. The energy requred to rase,000 pounds a dstance of one foot n one mnute. hp s equal to watts, or 0. kw. H pot: A standard test on dry-type transformers consstng of extra-hgh potentals (voltages) connected to the wndngs. Used to check the ntegrty of nsulaton materals and clearances. Hottest-spot temperature: The hghest temperature nsde the transformer wndng. Is greater than the measured average temperature of the col conductors, when usng the resstance change method. Hysteress: The tendency of a magnetc substance to persst n any state of magnetzaton. Impedance: The retardng forces of current n an AC crcut; the current-lmtng characterstcs of a transformer. Symbol = Z Inductance: In electrcal crcuts, the opposton to a change n the flow of electrcal current. Symbol = L Inducted potental test: A standard delectrc test of transformer nsulaton. Verfes the ntegrty of nsulatng materals and electrcal clearances. Inrush current: The ntal hgh peak of current that occurs n the frst few cycles of energzaton, whch can be 0 to 0 tmes the rated current. Insulatng transformer: Another term for an solatng transformer. Insulaton: Materal wth a hgh electrcal resstance. Insulaton materals: Those materals used to nsulate the transformer s electrcal wndngs from each other and ground. Integral TVSS or SPD: Major Standard Change for Surge Protectve Devces (formerly known as Transent Voltage Surge Suppressors). The prmary safety standard for transent voltage surge suppressors (TVSS) has undergone major revsons n the past three years wth mandatory complance by manufacturers requred by September, 00. Even the name of the standard has changed from UL Standard for Safety for Transent Voltage Surge Suppressors, UL to UL Standard for Safety for Surge Protectve Devces, UL. Ths means that TVSS lsted to the UL nd Edton standard wll no longer be able to be manufactured after September, 00. All Surge Protectve Devces must be desgned, tested, manufactured and lsted to the UL rd Edton standard after ths date. 0 0 CA0000E For more nformaton, vst:

4 .0- Dstrbuton Dry-Type TransformersLow Voltage Glossary Aprl 0 Sheet Isolatng transformer: A transformer where the nput (prmary) wndngs are not connected to the output (secondary) wndngs (.e., electrcally solated). K-factor: A common ndustry term for the amount of harmoncs produced by a gven load. The larger the K-factor, the more harmoncs that are present. Also used to defne a transformer s ablty to wthstand the addtonal heatng generated by harmonc currents. kva: Klovolt-ampere. Desgnates the output that a transformer can delver for a specfed tme at a rated secondary voltage and rated frequency wthout exceedng the specfed temperature rse. When multpled by the power factor, wll gve klowatts or kw. 000 VA = kva Lamnaton: Thn sheets of electrcal steel used to construct the core of a transformer. Lmtng temperature: The maxmum temperature at whch a component or materal may be operated contnuously wth no sacrfce n normal lfe expectancy. Lnear load: A load where the current waveform conforms to that of the appled voltage, or a load where a change n current s drectly proportonal to a change n appled voltage. Lve part: Any component consstng of an electrcally conductve materal that can be energzed under condtons of normal use. Load losses: I R losses n wndngs. Also see conductor losses. Low voltage wndng: In a twowndng transformer, the wndng ntended to have the lesser voltage. Usually marked wth X desgnatons. Md-tap: See center tap. Nose level: The relatve ntensty of sound, measured n decbels (db). NEMA Standard ST-0 outlnes the maxmum allowable nose level for dry-type transformers. Nonlnear load: A load where the current waveform does not conform to that of the appled voltage, or where a change n current s not proportonal to a change n appled voltage. Non-ventlated transformer: A transformer where the core and col assembly s mounted nsde an enclosure wth no openngs for ventlaton. Also referred to as totally enclosed non-ventlated (TENV). No load losses: Losses n a transformer that s excted at rated voltage and frequency but that s not supplyng a load. No load losses nclude core losses, delectrc losses and conductor losses n the wndng due to the exctng current. Also referred to as exctaton losses. Overload capablty: Short-term overload capacty s desgned nto transformers as requred by ANSI. Contnuous overload capacty s not delberately desgned nto a transformer because the desgn objectve s to be wthn the allowed wndng temperature rse wth nameplate loadng. Percent IR (% resstance): Voltage drop due to resstance at rated current n percent of rated voltage. Percent IX (% reactance): Voltage drop due to reactance at rated current n percent of rated voltage. Percent IZ (% mpedance): Voltage drop due to mpedance at rated current n percent of rated voltage. Phase: Type of AC electrcal crcut; usually sngle-phase two- or three-wre, or three-phase three- or four-wre. Polarty test: A standard test on transformers to determne nstantaneous drecton of the voltages n the prmary compared to the secondary. Prmary taps: Taps added to the prmary (nput) wndng. See Tap. Prmary voltage: The nput crcut voltage. Power factor: The cosne of the phase angle between a voltage and a current. Rato test: A standard test of transformers to determne the rato of the nput (prmary) voltage to the output (secondary) voltage. Reactance: The effect of nductve and capactve components of a crcut producng other than unty power factor. Reactor: A sngle wndng devce wth an ar or ron core that produces a specfc amount of nductve reactance nto a crcut. Normally used to reduce of control current. Regulaton: Usually expressed as the percent change n output voltage when the load goes from full load to no load. Scott T connecton: Connecton for three-phase transformers. Instead of usng three sets of cols for a threephase load, the transformer uses only two sets of cols. Seres/multple wndng: A wndng consstng of two or more sectons that can be connected for seres operaton or multple (parallel) operaton. Also called seres-parallel wndng. Short crcut: A low resstance connecton, usually accdental, across part of a crcut, resultng n excessve current flow. Sound levels: All transformers make some sound manly due to the vbraton generated n ts core by alternatng flux. All Eaton generalpurpose dry-type dstrbuton transformers are desgned wth sound levels lower than NEMA ST-0 maxmum levels. Star connecton: Same as a wye connecton. Step-down transformer: A transformer where the nput voltage s greater than the output voltage. Step-up transformer: A transformer where the nput voltage s less than the output voltage. T-T connecton: See Scott T connecton. Tap: A connecton brought out of a wndng at some pont between ts extremtes, usually to permt changng the voltage or current rato. Taps are typcally used to compensate for above or below rated nput voltage, n order to provde the rated output voltage. See FCAN and FCBN. Temperature class: The maxmum temperature that the nsulaton system of a transformer can contnuously wthstand. The common nsulaton classes are 0,, 0 (also ) and 0. Temperature rse: The ncrease over ambent temperature of the wndngs due to energzng and loadng the transformer. For more nformaton, vst: CA0000E

5 Aprl 0 Sheet 00 Dstrbuton Dry-Type TransformersLow Voltage Glossary and The Energy Polcy Act of Total losses: The sum of the no-load losses and load losses. Totally enclosed non-ventlated enclosure: The core and col assembly s nstalled nsde an enclosure that has no ventlaton to cool the transformer. The transformer reles on heat to radate from the enclosure for coolng. Transformer tests: Per NEMA ST-0, routne transformer producton tests are performed on each transformer pror to shpment. These tests are: Rato tests on the rated voltage connecton; Polarty and Phase Relaton tests on the rated connecton; No-Load and Exctaton Current tests at rated voltage on the rated voltage connecton and Appled Potental and Induced Potental tests. Specal tests nclude sound level testng. Transverse mode: Electrcal nose or voltage dsturbance that occurs between phase and neutral, or from spurous sgnals across metallc hot lne and the neutral conductor. Turns rato: The rato of the number of turns n the hgh voltage wndng to that n the low voltage wndng. Typcal test data: Tests that were performed on smlar unts that were prevously manufactured and tested. UL (Underwrters Laboratores): An ndependent safety testng organzaton. Unversal taps: A combnaton of sx prmary voltage taps consstng of at +-/% FCAN and at --/% FCBN. Watt: A unt of electrcal power when the current n a crcut s one ampere and the voltage s one volt. Wye connecton: A standard threewre transformer connecton wth smlar ends of sngle-phase cols connected together. The common pont forms the electrcal neutral pont and may be grounded. Also referred to as three-phase four-wre. To obtan the lne-to-neutral voltage, dvde the lne voltage by (.). The Energy Polcy Act of 00 The Energy Polcy Act of 00 and the resultng federal law 0 CFR Part (00) requre that effcency of low voltage dry-type dstrbuton transformers manufactured between January, 00 and December, 0 shall be no less than the effcency levels lsted n Table - of NEMA Standard TP--00. The U.S. Department of Energy passed a revson to 0 CFR Part n 0, mandatng hgher effcency levels for dstrbuton transformers manufactured startng January, 0. Transformers manufactured startng on ths date, for nstallaton n the U.S., must meet the new effcences detaled n 0 CFR Part (0), commonly referred to as DOE 0 effcency. Transformers specfcally excluded from the scope of ths law nclude: Transformers rated less than kva Transformers wth a prmary or secondary voltage greater than 00 V Transformers rated for operaton at other than 0 Hz Transformers wth a tap range greater than 0% Motor drve solaton transformers Rectfer transformers Autotransformers Transformers that supply Unnterruptble Power Supples Specal mpedance transformers Regulatng transformers Sealed and non-ventlated transformers Machne tool transformers Weldng transformers Groundng transformers Testng transformers Repared transformers Table.0-. Low Voltage Dry-Type Dstrbuton Transformer Effcency Table (%) Three-Phase kva NEMA TP- (Natonal Standard //00 //0).0. NEMA CSL DOE 0 Premum (Natonal Standard //0) Table.0-. DOE 0 Mnmum Effcency Levels for Low Voltage Dry-Type Dstrbuton Transformers Sngle-Phase Three-Phase kva Effcency % kva Effcency % CA0000E For more nformaton, vst:

6 .0- Dstrbuton Dry-Type TransformersLow Voltage Aprl 0 Sheet Ths page ntentonally left blank. For more nformaton, vst: CA0000E

7 Aprl 0 Sheet 00 Dstrbuton Dry-Type Transformers Overvew General Descrpton/Product Overvew.- DOE 0 Energy-Effcent Transformers K-Factor Rated Nonlnear Transformers Harmonc Mtgatng Transformers 0 CFR Part Energy-Effcent Ventlated Transformer Eaton s famly of energy-effcent ventlated transformers meet DOE 0 effcency requrements and federal energy effcency laws mandated by the Energy Polcy Act of 00 and 0 CFR Part (0). Dstrbuton transformers nstalled n the Unted States are requred to meet these energy effcency requrements. Energy-effcent transformers are especally desgned to have low no load (core) losses. Mnmum effcency levels have been establshed for these transformers when loaded at % of ther full load capacty. Avalable 00 V. Eaton offers a wde varety of energyeffcent transformers, ncludng C, C or 0 C; general purpose or K-factor rated; wth alumnum or copper wndngs. Eaton s energy-effcent transformers are manufactured wth a NEMA enclosure as standard, and are sutable for nstallaton outdoors when a NEMA R weathersheld kt s nstalled. Eaton s energy-effcent transformers use a 0 C nsulaton system wth C temperature rse as standard. Installaton of energy-effcent transformers may help facltes earn ponts toward LEED certfcaton from the U.S. Green Buldng Councl. Ventlated Transformer Eaton K-Factor nonlnear transformers are specfcally desgned to wthstand the harmful overheatng effects caused by harmoncs generated by nonlnear (non-snusodal) loads. These loads nclude computers, laser prnters, copers and other offce equpment, as well as vdeo montors and other electronc equpment. The core and cols of K-Factor transformers are especally desgned to have reduced nducton levels, whch result n a reducton n stray losses. Overszed (00% rated) neutrals and electrostatc sheldng are provded as standard on K-Factor transformers. Eaton K-Factor transformers are avalable n ratngs wth a K-factor of,,, 0, 0, 0 and. 00 V-class sngle-phase models are avalable to kva; three-phase ratngs to 0 kva. Eaton s famly of K-Factor transformers are manufactured wth the same hghqualty constructon features as our ventlated transformer products, ncludng NEMA enclosures and the 0 C (Class R) nsulaton system wth C temperature rse as standard. Refer to Page.-0 for addtonal nformaton. Eaton K-Factor rated transformers are avalable to meet all 0 CFR Part effcency levels, ncludng DOE 0 effcency. Harmonc Mtgatng Ventlated Transformer Eaton s harmonc mtgatng transformers (HMTs) are specally desgned transformers that treat a wde varety of harmoncs. Also called phaseshftng transformers, ther low zerosequence mpedance wye zg-zag secondary wndngs prevent harmful trplen (rd, th, th, etc.) harmonc currents from couplng nto the prmary delta, where they can progress upstream to the servce entrance. Multple HMTs wth a varety of phaseshft confguratons can be appled n a coordnated scheme to target th, th, and hgher order harmoncs at the common bus feedng all of the transformers. HMTs are deally suted for nstallatons rch n harmonc loads, such as educatonal facltes (K- and unverstes), government, commercal, medcal and call-center applcatons. HMTs are manufactured wth the same hgh-qualty features as Eaton s ventlated transformers, ncludng NEMA enclosures and the 0 C (Class R) nsulaton system wth C temperature rse as standard. Addtonally, Eaton s HMTs are manufactured wth a 00% neutral and electrostatc sheld as standard. Refer to Page.- for addtonal nformaton. HMTs are avalable n four confguratons: Type NON (0 phase-shft) Type THR (0 ) Type POS (+ ) Type NEG ( ) Avalable n three-phase ratngs to 000 kva and 00 V. Eaton HMTs are avalable to meet all 0 CFR Part effcency levels, ncludng DOE 0 effcency. 0 0 CA0000E For more nformaton, vst:

8 .- Dstrbuton Dry-Type Transformers Overvew General Descrpton/Product Overvew Aprl 0 Sheet 00 Motor Drve Isolaton Transformers Hazardous Locaton Transformers Mn Power Center 0 Motor Drve Isolaton Ventlated Transformer Eaton s motor drve solaton transformers are especally desgned for three-phase, SCR-controlled, varablespeed motor drve load profles. Szed by horsepower and common motor voltages, motor drve solaton transformers are braced to wthstand the mechancal stresses assocated wth AC adjustable frequency drves or DC drves. Avalable n three-phase ventlated desgns to 0 hp and 00 V. Epoxy encapsulated threephase desgns are avalable to 0 hp. Motor drve solaton transformers are manufactured usng the same hghqualty constructon features as our ventlated transformer products, ncludng NEMA enclosures and the 0 C (Class R) nsulaton system wth C temperature rse as standard. Epoxy encapsulated models have NEMA R enclosures and C temperature rse as standard. All Eaton three-phase ventlated motor drve solaton transformers nclude a normally open dry contact temperature sensor nstalled n the cols; encapsulated models are not avalable wth ths sensor. Ths sensor can be connected to provde advance alert or warnng of a potental overheatng of the transformer. Refer to Page.- for addtonal nformaton. Read the text on Page.0- on the Energy Polcy Act of 00 before specfyng these unts. These unts are exempt from 0 CFR Part effcency requrements. Hazardous Locaton Transformers Eaton s hazardous locaton transformers are sutable for use n envronments classfed by the Natonal Electrcal Code (NEC ) as Class I, Dvson, Groups A, B, C and D, as defned by NEC Artcle, when nstalled n complance wth NEC-recommended procedures for dry-type transformers rated 00 V and below. As defned by NEC Artcle 0, Class I, Dvson locatons nclude atmospheres that may contan volatle or gntable concentratons of flammable lquds or gas vapors, or locatons adjacent to such envronments. Acetone, ammona, benzene, gasolne, methane, propane and natural gas are examples of such substances. Eaton s hazardous locaton transformers are of the encapsulated desgn, and are avalable up to 00 V ratngs. Snglephase ratngs 0.0 kva through kva; three-phase ratngs to. kva. Alumnum wndngs are standard, wth copper as an opton. Hazardous locaton transformers use a 0 ºC nsulaton system wth ºC temperature rse as standard. 0 ºC rse s an avalable opton. Refer to Page.- for addtonal nformaton. Mn Power Center An Eaton mn power center replaces three ndvdual components: Prmary man breaker Transformer Dstrbuton loadcenter. The mn power center combnes all three nto a sngle unt. All nterconnectng wrng s performed at the factory. Mn power centers are deally suted for applcatons where 0 V s requred at a remote locaton. Parkng lots, workbenches and temporary power on constructon stes are common applcatons for mn power centers. Avalable n sngle-phase and three-phase ratngs to 00 V, 00 A, and 0 kva wth secondary loadcenters wth provsons for up to sngle-pole branch breakers. Avalable wth alumnum bus and plug-on branch breakers, or wth copper bus and bolt-on branch breakers. Mn power centers ncorporate an encapsulated transformer n ther constructon, and are NEMA R rated for outdoor applcatons. Eaton s mn power centers are UL Lsted for use as servce entrance devces. Refer to Page.- for addtonal nformaton. 0 For more nformaton, vst: CA0000E

9 Aprl 0 Sheet 00 Dstrbuton Dry-Type Transformers Overvew General Descrpton/Product Overvew.- Shelded Isolaton Transformers Marne Duty Transformers Buck-Boost and Low Voltage Lghtng Transformers Shelded Isolaton Ventlated Transformer Eaton s shelded solaton transformers are typcally nstalled where senstve loads such as nput crcuts of computers, medcal equpment and mcroprocessors requre addtonal protecton from hgh-frequency electrcal dsturbances. Shelded solaton transformers nclude an electrostatc sheld (Faraday sheld) nstalled between the prmary and secondary wndngs. Ths sheld s grounded to the core of the transformer to attenuate hgh-frequency electrcal dsturbances n the load from beng transmtted to the lne sde of the transformer. Shelded solaton transformers are avalable n all szes and ratngs of encapsulated and ventlated transformers. By desgn, all K Factor and harmonc mtgatng transformers nclude a sngle, alumnum electrostatc sheld as standard. Shelded solaton transformers are avalable that meet 0 CFR Part (DOE 0) effcency requrements. Read the text on Page.0- on the Energy Polcy Act of 00 before specfyng these unts. Marne-Duty Ventlated Transformer Eaton s marne-duty transformers are Type Approved by the Amercan Bureau of Shppng (ABS) for on-board use n steel vessels (not for propulson systems or combat vessels). These transformers are typcally nstalled below deck n electrcal or mechancal rooms where the ambent temperature s greater than normal. Eaton s marneduty transformers are especally desgned for operaton n C ambent locatons. Marne-duty rated transformers are manufactured wth copper wndngs as standard. Encapsulated desgns are avalable n sngle-phase ratngs 0.0 kva through. kva; three-phase desgns kva through. kva. Ventlated desgns are avalable n sngle-phase ratngs of kva through kva; three-phase desgns kva through 000 kva. Encapsulated and ventlated models are avalable up to 00 V ratngs. The standard temperature rse of Eaton s marne-duty transformers s C. Read the text on Page.0- on the Energy Polcy Act of 00 before specfyng these unts. Buck-Boost Transformers Eaton s buck-boost transformers are deally suted to applcatons where the avalable voltage needs to be slghtly ncreased ( boosted ) or decreased ( bucked ) to be used n a specfc applcaton. When buckboost transformers are wred as autotransformers, they can be used to accomplsh ths buckng or boostng of voltage. Buck-boost transformers are sngle-phase encapsulated transformers and are avalable n three voltage combnatons; 0 x 0 / 0 x 0 / 0 x 0 /...and are avalable n 0.0 kva through. kva. These transformers can also be used at ther nameplate voltages for applcatons such as low voltage nteror or landscape lghtng. 0 0 CA0000E For more nformaton, vst:

10 .- Dstrbuton Dry-Type Transformers General Purpose Ventlated Transformers Descrpton Aprl 0 Sheet 00 0 General Constructon Features of General Purpose (DOE 0, ncludng K-Factor DOE 0 and HMT DOE 0) Ventlated Transformers Rated 00 V and below General Descrpton Eaton s sngle-phase and three-phase general purpose dry-type ventlated transformers are of the two-wndng type, self-cooled, and are avalable n a wde varety of prmary and secondary voltage combnatons. Eaton s transformers are desgned, manufactured and tested n accordance wth all of the latest applcable ANSI, NEMA and IEEE standards. All 00 V class ventlated transformers wth ratngs through 0 kva are UL lsted and bear the UL label. Open core and col assembles are UR labeled products. These transformers are desgned for contnuous operaton at rated kva for hours a day, days a year, wth normal lfe expectancy as defned n ANSI C.. Effcency valdaton: Eatonmanufactured transformers n complance wth 0 CFR Part (0), DOE 0 effcent bear the UL Energy Effcency Verfcaton Mark to confrm that the transformer meets the energy effcency requrements set forth n federal law 0 CFR Part. Insulaton System Industry standards classfy nsulaton systems and temperature rse as shown below. Table.-. Insulaton System Classfed Ambent Temperature 0 C 0 C 0 C + Wndng Rse 0 C C C + Hot Spot 0 C 0 C 0 C = Temp. Class C C 0 C The desgn lfe of transformers havng dfferent nsulaton systems s the same; the lower temperature systems are desgned for the same lfe as the hgher temperature systems. Most Eaton ventlated transformers, regardless of ther temperature rse, are manufactured usng a 0 C nsulaton system. Requred performance s obtaned wthout exceedng the nsulaton system ratng at rated temperature rse n a 0 C maxmum ambent, wth an average ambent temperature of 0 C over a -hour perod. Transformers manufactured wth 0C nsulaton system meet the requrements of NEC 0.(b) Excepton No.. It s not necessary to nstall them n a specal, freresstant room. All nsulaton materals used are flame-retardant and do not support combuston as defned n ASTM Standard Test Method D. Core and Col Assembles The transformer core s constructed usng hgh-grade, non-agng, slcon steel wth hgh magnetc permeablty, and low hysteress and eddy current losses. Maxmum magnetc flux denstes are substantally below the saturaton pont. The transformer core volume allows for effcent transformer operaton at 0% above the nomnal tap voltage. The core lamnatons are tghtly clamped and compressed. Cols are wound of electrcal grade alumnum or copper, and are of contnuous wound constructon. The BIL (basc mpulse level) for all 00 V-class wndngs s 0 kv. The core and col assembly s nstalled on neoprene vbratonabsorbng pads. Ventlated transformers wth wyeconnected secondares have the neutral brought out to a separate XO termnal or busbar. The core and col assembly s grounded to the transformer enclosure by means of a vsble flexble copper ground strap. The copper ground strap s szed per the NEC to be a groundng conductor. Eaton three-phase DOE 0 effcent transformers are provded wth a bondng ground bar attached to the bottom panel for complance wth NEC 0.0(A). Electrostatc Sheldng There are no ndustry standards for electrostatc sheld performance. Eaton-manufactured transformers have been tested by an ndependent laboratory to meet the followng attenuaton levels: When tested per MIL-Std-0A, Method of Inserton Loss Measurement, wth matched mpedance no load technque:. Common mode nose attenuaton: Mnus 0 dba mnmum at 0. khz to. khz; mnus dba mnmum at. khz to 00 khz.. Normal mode (Transverse mode) nose attenuaton: Mnus dba mnmum at. khz to 0 khz. Prmary to Secondary Capactance of..0 pcofarads on the range 00 0 khz. 0 For more nformaton, vst: CA0000E

11 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Ventlated Transformers Descrpton.- Taps Prmary taps are avalable on most Eaton ventlated transformers to allow compensaton for source voltage varatons. Wndng Termnatons Prmary and secondary wndngs are termnated n the wrng compartment. Encapsulated unts have copper leads or stabs brought out for connectons. Ventlated transformers have leads brought out to alumnum or copper pads that are pre-drlled to accept Cu/Al lugs. Alumnum-wound transformers have alumnum pads; copperwound transformers have copper pads. Lugs are not suppled wth Eaton transformers; however, lug kts are avalable as a feld-nstalled accessory. Eaton recommends external cables be rated 0 C (szed at C ampacty) for encapsulated desgns and rated C for ventlated desgns. Seres-Multple Wndngs Seres-multple wndngs consst of two smlar cols n each wndng that can be connected n seres or parallel (multple). Transformers wth seresmultple wndngs are desgnated wth an x or a / between the voltage ratngs, such as voltages of 0 x 0 or 0/0. If the seres-multple wndng s desgnated by an x, the wndng can be connected only n seres or parallel. Wth a / desgnaton, a md-pont also becomes avalable n addton to the seres or parallel connecton. As an example, a 0 x 0 wndng can be connected for ether 0 (parallel) or 0 (seres). A 0/0 wndng can be connected for ether 0 (parallel) or 0 (seres), or 0 wth a 0 md-pont. Enclosures The transformer enclosure s made of heavy-gauge steel and s fnshed usng a contnuous process of degreasng, cleanng and phosphatzng, followed by electrostatc deposton of a thermosettng polyester powder coatng and subsequent bakng. The coatng color s ANSI and s UL recognzed for outdoor use. In complance wth NEMA ST-0, Eaton s ventlated transformers are desgned such that the maxmum temperature on the top of the enclosure does not exceed C rse above the ambent temperature. For ventlated transformers, the enclosure constructon s ventlated, drp-proof, NEMA, wth lftng provsons. CA0000E All ventlaton openngs are protected aganst fallng drt. Proper nstallaton of weathershelds on ventlated transformers makes the enclosure NEMA R rated and sutable for outdoor use. To ensure proper ventlaton and coolng of the transformer, follow manufacturer s recommended clearances around ventlaton openngs. Installaton Clearances Eaton s transformers should be nstalled wth a mnmum clearance around the transformer enclosure to prevent accdental contact wth flammable or combustble materals. The mnmum requred clearance from the back panel vares by transformer desgn. Many small kva ventlated transformers ( kva and smaller) requre just nches of clearance, whle larger kva transformers requre -nch clearance or more. Mnmum nstallaton clearances are stated on the nameplate of all transformers. The NEC requres a mnmum of nches clearance n front of the transformer for safe nstallaton and mantenance. Care should be taken to avod restrctng the arflow through the bottom of the transformer. Transformers should be located n areas not accessble to the publc. Sound Levels All transformers emt some audble sound due manly to the vbraton generated n ther core by alternatng flux. NEMA ST-0 defnes the maxmum average sound levels for transformers. For more nformaton, vst: All Eaton ventlated transformers are desgned to have audble sound levels lower than those requred by NEMA ST-0 (0). However, consderaton should be gven to the specfc locaton of a transformer and ts nstallaton to mnmze the potental for sound transmsson to surroundng structures and sound reflecton. Installaton and ambent condtons at a specfc locaton can result n feld-measured audble sound levels as much as dba greater than those levels measured n a sound-proof chamber. The followng nstallaton methods should be consdered:. If possble, mount the transformer away from corners of walls or celngs. For nstallatons that must be near a corner, use sound-absorbng materals on the walls and celng f necessary to elmnate reflecton.. Provde a sold foundaton for mountng the transformer and use vbraton dampenng mounts f not already provded n the transformer. Eaton s ventlated transformers contan a bult-n vbraton dampenng system to mnmze and solate sound transmsson. However, supplemental vbraton dampenng mounts nstalled between the floor and the transformer may provde addtonal sound dampenng. Table.-. NEMA ST-0 (0) Maxmum Audble Sound Levels for 00 V Class Transformers (dba) Equvalent Average Sound Level, Decbels Wndng kva Self-Cooled Ventlated Self-Cooled Sealed Range A B C D.00 and below.0 to.00.0 to.00.0 to to.00.0 to.00.0 to.. to.00.0 to.00.0 to to to to K Factor = K Factor = K Factor = K Factor = K Factor = Forced Ar When Fans Runnng Greater than 000 Consult factory Note: Consult factory for nonlnear requrements exceedng a K-factor ratng of 0. When the fans are not runnng, columns A and B apply. Sound levels are measured usng the A-weghted scale (dba). 0 0

12 .- Dstrbuton Dry-Type Transformers Ventlated Transformers Descrpton Aprl 0 Sheet Make electrcal connectons to the transformer usng flexble condut.. Locate the transformer n an area where audble sound s not offensve to buldng nhabtants.. If a transformer s gong to be nstalled n a locaton where the audble sound could be objectonable, consder nstallng a transformer specfcally desgned to have reduced sound levels. Eaton offers many transformers wth a sound reducton up to db below NEMA ST-0 lmts. Applcable Standards 00 V-class ventlated transformers are manufactured per the followng standards: UL NEMA ST-0 ANSI C..0 IEC 0 for CE-marked ventlated models Sesmc Qualfcaton Refer to Tab for nformaton on sesmc qualfcaton for ths and other Eaton products. Standard Producton Tests The followng producton tests are performed as standard on all Eaton transformers, pror to shpment:. Rato tests at the rated voltage connecton and at all tap connectons.. Polarty and phase relaton tests on the rated voltage connecton.. Appled potental tests.. Induced potental tests.. No-load and exctaton current at rated voltage on the rated voltage connecton. Operaton Eaton s ventlated transformers are desgned for contnuous operaton at rated kva for hours a day, days a year, wth normal lfe expectancy as defned n ANSI C.. Short-term overload capacty s desgned nto transformers, as requred by ANSI. Ventlated transformers wll delver 00% of nameplate load for 0 mnutes; % of nameplate load for hour; and % of nameplate load for hours wthout beng damaged, provded that a constant % load precedes and follows the overload. Refer to ANSI C.-0. for addtonal lmtatons. Note: Contnuous overload capacty s not delberately desgned nto transformers. The desgn objectve s to be wthn the allowable wndng temperature rse at nameplate full load capacty. However, because Eaton s ventlated transformers are manufactured usng a 0 C nsulaton system, C and 0 C low temperature rse transformers can be operated as C rse transformers. The excess thermal capacty of these low temperature rse transformers allows a C transformer to be operated as a C rse transformer and overloaded by % of ts nameplate kva wthout compromsng the normal lfe of the transformer. Lkewse, an 0 C rse transformer operated as a C rse transformer s capable of a constant 0% overload wthout compromsng the normal lfe expectancy of the transformer. Table.-. Rated Lne Amperes for kva and Voltages of Sngle-Phase Transformers kva Rated Lne Voltage Ratng Note: Lne Current = (kva x 000)/Lne Voltage Table.-. Rated Lne Amperes for kva and Voltages of Three-Phase Transformers kva Rated Lne Voltage Ratng Note: Three-Phase Lne Current = (kva x 000)/(Lne Voltage x.) For more nformaton, vst: CA0000E

13 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers General Purpose Encapsulated Transformers Descrpton.- General Constructon Features of General Purpose Encapsulated Transformers Rated 00 V and Below General Descrpton Eaton s sngle-phase and three-phase general purpose encapsulated dry-type transformers are of the two-wndng type, self-cooled, and are avalable n a wde varety of prmary and secondary voltage combnatons. Eaton s transformers are desgned, manufactured and tested n accordance wth all of the latest applcable ANSI, NEMA and IEEE standards. All 00 V- class encapsulated transformers wth ratngs through. kva are UL lsted and CSA certfed, and bear the UL and CSA labels. These transformers are desgned for contnuous operaton at rated kva for hours a day, days a year, wth normal lfe expectancy as defned n ANSI C.. Encapsulated transformers are outsde the scope of U.S. energy effcency law 0 CFR Part (DOE 0). Insulaton Systems Industry standards classfy nsulaton systems and temperature rse as shown below. Table.-. Insulaton System Classfcaton Ambent Temperature 0 C 0 C C 0 C 0 C + Wndng Rse C 0 C C C C + Hot Spot 0 C 0 C 0 C 0 C 0 C = Temp. Class 0 C C 0 C C 0 C The desgn lfe of transformers havng dfferent nsulaton systems s the same; the lower temperature systems are desgned for the same lfe as the hgher temperature systems. Eaton s encapsulated transformers are manufactured usng a 0 C nsulaton system. Requred performance s obtaned wthout exceedng the nsulaton system ratng at rated temperature rse n a 0 C maxmum ambent, wth an average ambent temperature of 0 C over a -hour perod. All nsulaton materals are flameretardant and do not support combuston as defned n ASTM Standard Test Method D. Core and Col Assembles The transformer core s constructed usng hgh-grade, non-agng, slcon steel wth hgh-magnetc permeablty, and low hysteress and eddy current losses. Maxmum magnetc flux denstes are substantally below the saturaton pont. The transformer core volume allows for effcent transformer operaton at 0% above the nomnal tap voltage. The core lamnatons are tghtly clamped and compressed. Cols are wound of electrcal grade alumnum or copper, and are of contnuous wound constructon. The BIL (basc mpulse level) for all 00 V-class wndngs s 0 kv. In encapsulated transformers, the core and col assembly s completely encased n a proportoned mxture of resn or epoxy, and aggregate to provde a mostureproof, shock-resstant seal. The core and col encapsulaton system s desgned to mnmze the audble sound level. Taps Prmary taps are avalable on many Eaton encapsulated transformers to allow compensaton for source voltage varatons. Wndng Termnatons Prmary and secondary wndngs are termnated n the wrng compartment. Encapsulated unts have copper leads or stabs brought out for connectons. Ventlated transformers have leads brought out to alumnum or copper pads that are pre-drlled to accept Cu/Al lugs. Alumnum-wound transformers have alumnum pads; copperwound transformers have copper pads. Lugs are not suppled wth Eaton s transformers; however, lug kts are avalable as a feld-nstalled accessory. Eaton recommends external cables be rated 0 C (szed at C ampacty) for encapsulated desgns and rated C for ventlated desgns. Seres-Multple Wndngs Seres-multple wndngs consst of two smlar cols n each wndng that can be connected n seres or parallel (multple). Transformers wth seres-multple wndngs are desgnated wth an x or a / between the voltage ratngs, such as voltages of 0 x 0 or 0/0. If the seresmultple wndng s desgnated by an x, the wndng can be connected only n seres or parallel. Wth a / desgnaton, a md-pont also becomes avalable n addton to the seres or parallel connecton. As an example, a 0 x 0 wndng can be connected for ether 0 (parallel) or 0 (seres). A 0/0 wndng can be connected for ether 0 (parallel) or 0 (seres), or 0 wth a 0 md-pont. Enclosures The transformer enclosure s made of heavy-gauge steel and s fnshed usng a contnuous process of degreasng, cleanng and phosphatzng, followed by electrostatc deposton of a thermosettng polyester powder coatng and subsequent bakng. The coatng color s ANSI and s UL recognzed for outdoor use. In complance wth NEMA ST-0, Eaton s transformers are desgned such that the maxmum temperature on the top of the enclosure does not exceed C rse above the ambent temperature. For encapsulated transformers, the standard enclosure constructon s totally enclosed, non-ventlated NEMA R, wth lftng provsons. NEMA X rated encapsulated transformers are avalable as an opton. Wall mountng brackets are provded on many Eaton encapsulated transformers. These mountng brackets are desgned to provde the proper spacng between the mountng surface and the transformer enclosure. To ensure proper ventlaton and coolng of the transformer, follow manufacturer s recommended clearances around encapsulated transformers. 0 0 CA0000E For more nformaton, vst:

14 .- Dstrbuton Dry-Type Transformers General Purpose Encapsulated Transformers Descrpton Aprl 0 Sheet Sound Levels All transformers emt some audble sound due manly to the vbraton generated n ther core by alternatng flux. NEMA ST-0 defnes the maxmum average sound levels for transformers. All Eaton encapsulated transformers are desgned to have audble sound levels lower than those requred by NEMA ST-0 (0). However, consderaton should be gven to the specfc locaton of a transformer and ts nstallaton to mnmze the potental for sound transmsson to surroundng structures and sound reflecton. Installaton and ambent condtons at a specfc locaton can result n feld-measured audble sound levels as much as dba greater than those levels measured n a sound-proof chamber. The followng nstallaton methods should be consdered:. If possble, mount the transformer away from corners of walls or celngs. For nstallatons that must be near a corner, use soundabsorbng materals on the walls and celng f necessary to elmnate reflecton.. Provde a sold foundaton for mountng the transformer and use vbraton-dampenng mounts f not already provded n the transformer. Eaton s encapsulated transformers use a specal encapsulaton system to mnmze and solate sound transmsson. However, supplemental vbraton dampenng mounts nstalled between the floor and the transformer may provde for addtonal sound dampenng.. Make electrcal connectons to the transformer usng flexble condut.. Locate the transformer n an area where audble sound s not offensve to buldng nhabtants.. If a transformer s gong to be nstalled n a locaton where the audble sound could be objectonable, consder nstallng a transformer specfcally desgned to have reduced sound levels. Eaton offers many transformers wth a sound reducton up to db below NEMA ST-0 lmts. Table.-. NEMA ST-0 (0) Maxmum Audble Sound Levels for 00 V Class Transformers (dba) Equvalent Average Sound Level, Decbels Wndng kva Self-Cooled Ventlated Self-Cooled Sealed Range A B C D.00 and below.0 to.00.0 to.00.0 to to.00.0 to.00.0 to.. to.00.0 to.00.0 to to to to K Factor = K Factor = K Factor = K Factor = K Factor = Forced Ar When Fans Runnng Greater than 000 Consult factory Note: Consult factory for nonlnear requrements exceedng a K-factor ratng of 0. When the fans are not runnng, columns A and B apply. Sound levels are measured usng the A-weghted scale (dba). For more nformaton, vst: CA0000E

15 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers General Purpose Encapsulated Transformers Descrpton.- Applcable Standards 00 V-class encapsulated transformers are manufactured per the followng standards: Encapsulated transformers are outsde the scope of energy effcency mandates, ncludng 0 CFR Part UL up to kva UL kva and larger NEMA ST-0 ANSI C..0 IEEE C..0 IEC for sngle-phase CE-marked models CSA C. No. -M0 Sesmc Qualfcaton Refer to Tab for nformaton on sesmc qualfcaton for ths and other Eaton products. Standard Producton Tests The followng producton tests are performed as standard on all Eaton transformers, pror to shpment:. Rato tests at the rated voltage connecton and at all tap connectons.. Polarty and phase relaton tests on the rated voltage connecton.. Appled potental tests.. Induced potental tests.. No-load and exctaton current at rated voltage on the rated voltage connecton. Operaton Eaton s encapsulated transformers are desgned for contnuous operaton at rated kva for hours a day, days a year, wth normal lfe expectancy as defned n ANSI C.. Short-term overload capacty s desgned nto transformers, as requred by ANSI. Encapsulated transformers wll delver 00% of nameplate load for 0 mnutes; % of nameplate load for hour; and % of nameplate load for hours wthout beng damaged, provded that a constant % load precedes and follows the overload. Refer to ANSI C.-0. for addtonal lmtatons. Note: Contnuous overload capacty s not delberately desgned nto transformers because the desgn objectve s to be wthn the allowable wndng temperature rse at nameplate full load capacty. Table.-. Rated Lne Amperes for kva and Voltages of Sngle-Phase Transformers kva Rated Lne Voltage Ratng Note: Lne Current = (kva x 000)/Lne Voltage Table.-. Rated Lne Amperes for kva and Voltages of Three-Phase Transformers kva Rated Lne Voltage Ratng Note: Three-Phase Lne Current = (kva x 000)/(Lne Voltage x.) CA0000E For more nformaton, vst:

16 .-0 Dstrbuton Dry-Type Transformers K-Factor Rated Nonlnear Transformers Descrpton Aprl 0 Sheet K-Factor Rated Nonlnear Transformers Rated 00 V and Below Applcatons Eaton K-Factor transformers are specfcally desgned to wthstand the harmful overheatng effects caused by harmoncs generated by nonlnear (non-snusodal) loads. These loads nclude computers, laser prnters, copers and other offce equpment, as well as vdeo montors and other electronc equpment. Eaton K-Factor transformers are not smply over-szed transformers. The core and cols of our K-Factor transformers are specally desgned to have reduced nducton levels, whch results n a reducton n stray losses. Overszed (00% rated) neutrals and electrostatc sheldng are typcal features found n our K-Factor transformers. Eaton K-Factor transformers are manufactured wth the same hgh-qualty constructon features as our other ventlated transformer products, ncludng NEMA enclosures as standard. Techncal Data Avalable Ratngs Eaton K-Factor transformers are avalable n a wde range of ratngs to meet specfc voltage converson requrements. Eaton offers transformers wth K-factor ratngs of,,, 0, 0, 0 and. kva Capacty Sngle-phase ventlated desgns are avalable n ratngs from kva through kva; three-phase ratngs kva through 0 kva. Insulaton System and Temperature Rse Eaton-manufactured ventlated transformers are manufactured usng a 0 C nsulaton system wth C temperature rse as standard. Low temperature rse desgns ( C and 0 C temperature rse) are avalable as optons. Frequency Most ventlated transformers are desgned to operate n 0 Hz systems. /0 Hz desgns are avalable as an opton. Eaton s ventlated transformers can be desgned to operate at a varety of frequences. Wndng Materal Alumnum conductor and termnatons are provded as standard on ventlated transformers. Copper wndng conductors and termnatons are avalable as an opton. Installaton Clearances Eaton s ventlated transformers should be nstalled wth mnmum clearances as noted on the transformer s nameplate. Most Eaton transformers requre a mnmum of nches clearance behnd the transformer; however, many small kva ventlated transformers may be nstalled wth just nches clearance, whle large kva transformers requre nches or more of clearance behnd the transformer. Mnmum nstallaton clearances are stated on the nameplate of all transformers. The NEC requres a mnmum of nches clearance n front of the transformer. Care should be taken to avod restrctng the arflow through the bottom of the transformer. Transformers should be located n areas not accessble to the publc. Wrng Compartment Eaton s ventlated transformers have wrng compartments szed to comply wth NEMA and NEC standards. The K-factor A common ndustry term for the amount of harmoncs produced by a gven load s the K-factor. The larger the K-factor, the more harmoncs are present. Lnear loads, for example, have a K-factor of. Transformers may carry a K-factor ratng to defne the transformer s ablty to wthstand the addtonal heatng generated by harmonc currents. Calculatng the K-factor All nonlnear waveforms can be broken down mathematcally nto a fundamental frequency and ts harmoncs. IEEE C.0 establshes a drect relatonshp between these harmoncs and transformer heatng. Underwrters Laboratores has establshed a smlar relatonshp, the K-factor, whch s derved by summng the square of the percentage current at a gven harmonc level multpled by the square of the harmonc order. K = ²( I h) (h) Ih = Percent Current at Harmonc h h = Harmonc Order,.e., rd, th, th For example, a load that s 0% of the fundamental, 0% of the thrd harmonc, and 0% of the ffth harmonc would yeld (.) () + (.) () + (.) () or a K-factor of.. Ths load would requre a transformer wth a K-factor ratng of. Transformers that carry a K-factor ratng defne the transformer s ablty to wthstand a gven harmonc load whle operatng wthn the transformer s nsulaton class. An analyss of harmonc loads and a calculaton of the K-factor must be made to properly apply transformers n any buldng or faclty. Note that the calculated K-factor s not constant snce nonlnear loads change throughout the day as equpment and lghtng s turned off and on. These harmonc loads also change over the lfe of the buldng or faclty as equpment s added or removed. Harmonc Currents Harmonc currents are found n nonlnear loads. These currents are generated by varous types of equpment ncludng swtchng mode power supples that abruptly swtch current on and off durng each lne cycle. Swtchng mode power supples or dode capactor power supples convert AC lne voltage to low voltage DC. Ths process accomplshed by chargng capactors durng each lne cycle wth narrow pulses of current that are tme-concdent wth lne voltage peaks. Examples of ths equpment nclude electronc ballasts for fluorescent lghtng, personal computers, prnters, fax machnes, electronc and medcal test equpment unnterruptble power supples and sold-state motor drves. Note: Nonlnear s synonymous wth the term non-snusodal. Fgure.-. Harmonc Currents Found n Nonlnear Loads Cause Wave Shape Dstorton and Create Added Stresses on Transformers For more nformaton, vst: CA0000E

17 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Harmonc Mtgatng Transformers Descrpton.- Harmonc Mtgatng Transformers Rated 00 V and Below Applcatons Eaton s harmonc mtgatng transformers (HMTs) are specally desgned transformers that treat a wde varety of harmoncs. Also called phaseshftng transformers, ther low zerosequence mpedance wye zg-zag secondary wndngs prevent harmful trplen (rd, th, th, etc.) harmonc currents from couplng nto the prmary delta, where they can progress upstream to the servce entrance. Multple HMTs wth a varety of phaseshft confguratons can be appled n a coordnated scheme to target th, th and hgher-order harmoncs at the common bus feedng all of the transformers. HMTs are deally suted for nstallatons rch n harmonc loads, such as educatonal facltes (K and unverstes), government, commercal, medcal and call-center applcatons. HMTs are manufactured wth the same hgh-qualty features as Eaton s ventlated transformers, ncludng NEMA enclosures and the 0 C (Class R) nsulaton system wth C temperature rse as standard. Addtonally, Eaton s HMTs are manufactured wth a 00% neutral and electrostatc sheld as standard. Eaton s harmonc mtgatng ventlated transformers are desgned prmarly for ndoor nstallatons. Ventlated transformers have NEMA enclosures as standard, and are sutable for nstallaton outdoors when NEMA R weathersheld kts are nstalled. Ventlated transformers are typcally floor-mounted on an elevated housekeepng pad. When properly supported, they are also sutable for wall mountng or trapeze-mountng from celngs. Techncal Data Avalable Ratngs Eaton s harmonc mtgatng transformers are avalable n a wde range of ratngs to meet specfc voltage converson requrements. Eaton s HMTs accept a three-phase three-wre nput and have a three-phase four-wre (phases and neutral) output. kva Capacty Three-phase ratngs kva through 000 kva. Insulaton System and Temperature Rse Eaton s harmonc mtgatng transformers are manufactured usng a 0 C nsulaton system wth C temperature rse as standard. Low temperature rse desgns ( C and 0 C temperature rse) are avalable as optons. Frequency Eaton s harmonc mtgatng transformers are desgned to operate n 0 Hz systems. /0 Hz desgns are avalable as an opton. The transformers can be desgned to operate at a varety of frequences. Wndng Materal Copper conductor and termnatons are provded as standard on harmonc mtgatng transformers. Alumnum wndng conductors and termnatons are avalable as an opton. Installaton Clearances Eaton s ventlated transformers should be nstalled wth mnmum clearances as noted on the transformer s nameplate. Most Eaton transformers requre a mnmum of nches clearance behnd the transformer; however, many small kva ventlated transformers may be nstalled wth just nches clearance, whle large kva transformers requre nches or more of clearance behnd the transformer. Mnmum nstallaton clearances are stated on the nameplate of all transformers. The NEC requres a mnmum of nches clearance n front of the transformer. Care should be taken to avod restrctng the arflow through the bottom of the transformer. Transformers should be located n areas not accessble to the publc. Wrng Compartment Eaton s ventlated transformers have wrng compartments szed to comply wth NEMA and NEC standards. Thermal Sensors Harmonc mtgatng transformers are avalable wth warnng and/or alarm thermal sensors mbedded n ther cols. Thermal sensors are normally open dry contacts that can be wred to provde a sgnal to remote locatons to ndcate a potental heatng problem wthn the transformer cols. Contacts are rated 0 C (warnng) and 00 C (alarm). Applcaton Consderatons Eaton offers harmonc mtgatng transformers wth four dfferent phase-shft optons: Type NON (0 phase-shft) Type POS (+ phase-shft) Type NEG ( phase-shft) Type THR ( 0 phase-shft) To select the proper HMT, the nonlnear load profle of a partcular applcaton must be known. Type NON (0 ) HMTs are deally suted for treatng rd and other trplen harmoncs that are the sgnature of sngle-phase nonlnear loads. Ths s the most common applcaton encountered. Type NON HMTs use electromagnetc flux cancellaton to cancel trplen harmoncs. There, harmoncs are treated n the secondary wndngs and prevented from couplng nto the prmary delta wndngs, where they may be transmtted upstream to the servce entrance locaton. Type NON HMTs can be deployed sngly to treat trplen harmoncs. As wth most other harmonc mtgatng methods, the closer the HMT can be nstalled to the load, the greater the beneft. Type POS (+ ) and Type NEG ( ) harmonc mtgatng transformers are typcally used together n coordnated pars to treat th, th and other harmoncs that are generated by threephase nonlnear loads. th, th and hgher order harmoncs pass through the harmonc mtgatng transformers, to a pont of common couplng; the frst common electrcal pont that s shared by the HMTs. At ths common pont, balanced portons of the th, th, etc., harmonc currents are canceled and prevented from flowng further upstream n the dstrbuton system. Type POS and Type NEG HMTs have nearly dentcal electrcal characterstcs, ncludng zerosequence and postve-sequence mpedance and reactance. The more closely matched the coordnated pars of transformers, the more thorough the harmonc cancellaton. Coordnated pars of Type NON and Type THR transformers, as well as coordnated pars of Type NON, Type THR, Type POS and Type NEG HMTs provde treatment of rd and other trplen harmoncs wthn ther secondary wndngs. Ths cancellaton s acheved by vrtue of ther wye zg-zag wndng confguraton. 0 0 CA0000E For more nformaton, vst:

18 .- Dstrbuton Dry-Type Transformers Harmonc Mtgatng Transformers Descrpton Aprl 0 Sheet Harmonc Mtgatng Transformers As our world becomes even more dependent on electrcal and electronc equpment, there s an ncreased lkelhood that operatons wll experence the negatve effects of harmonc dstorton. The productvty and effcency gans acheved from ncreasngly sophstcated peces of equpment have a drawback: ncreased harmonc dstorton n Fgure.-. Typcal Waveform of Sngle-Phase Devces Fgure.-. Composte Waveform th rd Fgure.-. Components of a Nonlnear Waveform the electrcal dstrbuton system. The dffcult thng about harmonc dstorton s determnng the source. Once ths task has been completed, the soluton can be easy. Harmonc mtgatng transformers (HMTs) are one of the many possble solutons to help elmnate these harmful harmoncs. th 0 Hz fundamental fundamental For more nformaton, vst: What are Harmoncs? An understandng of how harmoncs are generated and what harmoncs really are s necessary n order to understand how HMTs can provde harmonc mtgaton. Electronc equpment requres DC voltage to operate. Rectfers and capactors are used to convert AC voltage to DC voltage wthn the equpment. These devces are frequently referred to as swtch mode power supples. As the capactors charge and dscharge durng ths converson, the capactor draws current n pulses, not at a contnuous rate. Ths rregular current demand, as depcted n Fgure.-, dstorts the lnear 0 Hz sne wave. As a result, these types of loads are commonly referred to as non-snusodal, or nonlnear. As shown n Fgures.- and.-, the waveform created by the nonlnear source s actually the mathematcal sum of several sne waves, each wth a dfferent frequency and magntude. Each of these ndvdual waveforms s called a harmonc, and s dentfed by ts frequency relatve to the fundamental frequency, 0 Hz. In other words, each ndvdual harmonc s dentfed by a number, whch s the number of complete cycles the specfc harmonc goes through n a sngle 0 Hz cycle. In Fgure.-, the fundamental frequency s 0 Hz. The fundamental frequency s assgned the harmonc number of, and s the benchmark for all other harmonc numberng. The fundamental, 0 Hz sne wave completes 0 full cycles n one second. The rd harmonc completes three full cycles n the tme t takes the fundamental to complete just one cycle, or 0 cycles per second. Lkewse, the th harmonc completes fve full cycles n the tme t takes the fundamental harmonc to complete a sngle cycle, whch equates to 00 cycles per second. Odd multples of the rd harmonc (rd, th,th, st, etc.) are commonly referred to as trplen harmoncs. The prolferaton of electronc equpment (ncludng computers, fax machnes, copers, electronc ballasts, offce equpment, cash regsters, slot machnes, electronc montorng devces, vdeo games, medcal dagnostc equpment and the lke) s what makes sngle-phase devces the most common source of harmoncs. These devces generate a typcal waveform shown n Fgure.-, and have a harmonc profle as shown n Table.-. As one can see, the predomnant harmonc s the rd harmonc. Three-phase, nonlnear loads such as drves, on the other hand, are typcally rch n th and th harmoncs. CA0000E

19 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Harmonc Mtgatng Transformers Descrpton.- What Problems do Harmoncs Cause? The dstorted current waveform that s created by nonlnear loads can cause many problems n an electrcal dstrbuton system. Dependng upon the severty of the harmonc dstorton, the negatve effects of harmoncs may be tolerable, and the nstallaton of a K-factor rated transformer may be an adequate soluton. K-factor rated transformers do not provde any harmonc treatment. Rather, they are desgned to wthstand the destructve effects of the addtonal heat generated by harmonc currents n the transformer s wndngs. In many nstances, the harmful effects of harmoncs are too severe, and smply toleratng them s not an acceptable opton. Harmonc currents can cause excessve heatng n dstrbuton transformers. Ths addtonal heat not only reduces the lfe expectancy of a transformer, t also reduces the usable capacty of the transformer. Another sde effect s that the audble nose of a transformer may be amplfed when nstalled n a system that contans harmoncs. An mportant characterstc of harmoncs s that they are transmtted upstream from the load, to the transformer s secondary wndngs, through the prmary wndngs of the transformer, back to the servce entrance, and eventually to the utlty lnes. Harmonc currents flowng upstream from nonlnear loads, through the system mpedance of cables and transformers, create harmonc voltage dstorton. When lnear loads, lke motors, are subjected to harmonc voltage dstorton, they wll draw a nonlnear harmonc current. As wth dstrbuton transformers, harmonc currents cause ncreased heatng, due to ron and copper losses, n motors and generators. Ths ncreased heatng can reduce the lfe of the motor, as well as the motor s effcency. In electrcal cables, harmonc currents may also create ncreased heatng, whch can lead to premature agng of the electrcal nsulaton. Nusance trppng of the crcut breakers protectng the cable may also occur. Communcatons equpment and data processng equpment are especally susceptble to the harmful effects of harmoncs because they rely on a nearly perfect snusodal nput. Ths equpment may malfuncton, or even fal, when nstalled n systems that are rch n harmoncs. The costs assocated wth downtme resultng from the malfuncton or falure of electrcal or electronc equpment can be staggerng. These costs can easly surpass thousands, f not mllons, of dollars per hour n lost producton or lost productvty. In addton to the well-defned costs assocated wth the most catastrophc of harmonc effects, there are many less quanttatve costs that are often overlooked when evaluatng the need for harmonc mtgaton. The ncreased heatng caused by harmoncs n cables, motors and transformers ncreases the coolng requrements n ar-condtoned areas. The same ncreases n heatng result n ncreased mantenance costs and more frequent equpment replacement n order to avod falures that could shut down a buldng for a perod of tme. What do HMTs do? HMTs are an economcal soluton n the battle aganst the harmful effects of harmoncs. HMTs are passve devces: they don t have any movng parts and they are typcally energzed hours a day, days a week, days a year. Ths means that they are always on the job treatng harmoncs, regardless of the level of load they are servng at a gven pont n tme. Whenever the HMT s energzed, t wll provde harmonc treatment. Harmonc mtgatng transformers are commonly referred to as phase-shftng transformers. The HMT offerng from Eaton s electrcal busness has delta-connected prmary wndngs and wye zg-zag connected secondary wndngs. The use of wye zg-zag secondary wndngs allows a transformer to be desgned n a wde varety of dfferent phase-shfts ( 0,, 0, + ). In standard delta-wye transformers, ncludng K-factor rated transformers, trplen harmoncs are passed from the secondary wndngs nto the prmary delta wndngs, where they are trapped and crculate. In HMTs, the electromagnetc flux cancellaton created by the wye zg-zag wndng confguraton prevents rd and other trplen harmoncs from beng transmtted nto the prmary delta wndng. Harmonc treatment s provded entrely by electromagnetc flux cancellaton; no flters, capactors or other such devces are used. It s mportant to remember that the harmonc currents stll flow n the secondary wndngs. 0 0 CA0000E For more nformaton, vst:

20 .- Dstrbuton Dry-Type Transformers Harmonc Mtgatng Transformers Descrpton Aprl 0 Sheet 00 0 Benefts of Installng HMTs In addton to mproved system relablty and reduced mantenance costs, HMTs also have excellent energy-savng characterstcs. Wth the cost of electrcty contnung to ncrease around the world, there s an ever-ncreasng nterest n energyeffcent products. In many facltes, the cost of electrcty s the second largest expense, eclpsed only by salares and wages. Transformers consume energy even when they are lghtly loaded or not loaded at all. Sgnfcant energy savngs may be attaned f the no-load losses of a transformer are reduced. 0 CFR Part addresses ths ssue by requrng hgh effcency levels when a transformer s loaded at % of ts full capacty. However, ths standard apples to lnear load profles only, and tests to valdate complance wth 0 CFR Part are performed usng lnear loads. In actual applcatons, the growng presence of electronc devces creates nonlnear load profles. Nonlnear loads cause the losses n dstrbuton transformers to ncrease, thereby reducng ther realzed effcency. Therefore, 0 CFR Part effcency complance may not be a true ndcaton of the effcency of a transformer exposed to nonlnear loads. Though a measure of lnear load effcency, Eaton s famly of HMTs meets the effcency standards set forth n 0 CFR Part. Because HMTs are ntended to be nstalled n systems that contan hgh levels of nonlnear loads, Eaton s famly of HMTs s desgned to meet the 0 CFR Part effcency levels when appled to nonlnear load profles wth 00% harmonc dstorton, across a broad range of load levels, not just the % load level used n 0 CFR Part. These energy savngs are realzed over the entre lfe of the transformer. Table.-. Typcal Harmonc Profle of Sngle-Phase Swtched Mode Power Supply Harmonc Magntude Applcaton Informaton The closer that an HMT can be located to the load, the greater the benefts of harmonc treatment. Installaton of a large capacty HMT at the servce entrance of a large buldng would certanly provde some harmonc treatment. However, nstallaton of several smaller rated HMTs, perhaps one or more on each floor of a buldng, provdes greater benefts that wll be notced throughout the faclty. For ths reason, the most popular HMTs wll be rated kva and less. Ths complements the cost-effcences that can be ganed by dstrbutng hgher voltages through smaller cables to the pont where a safer, lower voltage s needed to operate equpment. When connectng the loads to the transformer, t s mportant to remember that the balanced porton of the harmonc loads wll be treated. To acheve the maxmum harmonc treatment, when consderng the trplen harmoncs that are treated n the secondary wndngs, each phase should be balanced, and the harmonc profle of the loads should be as smlar as possble. When treatng th, th and hgher order harmoncs by usng multple transformers, the loads should lkewse have smlar harmonc profles, and the kva and mpedance of the transformers should be dentcal as well. For example, two kva HMTs can be pared wth a sngle kva HMT to provde maxmum harmonc performance. In nstances where transformers of unequal kva are used n combnaton, harmonc treatment s provded for the lowest kva load. For example, f, nstead of parng two kva HMTs wth a sngle kva HMT, one would par two kva HMTs wth a kva HMT. Only 0 kva (two tmes kva) of the kva load would be treated (f they were fully loaded). In real-world stuatons, t s nearly mpossble to have perfectly matched loads. However, the benefts of treatng harmoncs, even n stuatons where the loads are unbalanced, are a far superor opton than to not treat them at all. Eaton HMT transformers comply wth applcable 0 CFR Part effcency standards. 0 For more nformaton, vst: CA0000E

21 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Motor Drve Isolaton Transformers Descrpton.- Motor Drve Isolaton Transformers Rated 00 V and Below Applcatons Eaton s motor drve solaton transformers are especally desgned for three-phase SCR controlled, varable speed motor drves load profles. Szed by horsepower and common motor voltages, motor drve solaton transformers are braced to wthstand the mechancal stresses assocated wth AC adjustable frequency drves or DC drves. Two-wndng drve solaton transformers provde: Electrcal solaton between the ncomng lne and the drve crcutry Voltage converson on nput lne to standard drve nput voltages Help to mnmze lne dsturbances caused by SCR frng Reduce short-crcut currents and voltage lne transents Motor drve solaton transformers are manufactured usng the same hgh-qualty constructon features as our ventlated transformer products, ncludng NEMA enclosures and the 0 C (Class R) nsulaton system as standard. Epoxy encapsulated models have NEMA R enclosures and C temperature rse as standard. All Eaton three-phase ventlated motor drve solaton transformers nclude a normally open dry contact temperature sensor nstalled n the cols. Ths sensor can be connected to provde advance alert or warnng of a potental overheatng of the transformer. Ventlated transformers are typcally floor-mounted on an elevated housekeepng pad. When properly supported, they are also sutable for wall mountng or trapezemountng from celngs. Encapsulated desgns are typcally wall-mounted through kva; larger desgns are floor-mount. Motor drve solaton transformers are outsde the scope of U.S. energy effcency federal law 0 CFR Part. However, motor drve solaton transformers are ncluded n the scope of energy effcency laws n other countres, such as Canada. Techncal Data Avalable Ratngs Eaton s motor drve solaton transformers are avalable n a wde range of ratngs to meet specfc voltage converson requrements. Avalable n three-phase ventlated desgns to 0 hp and 00 V; epoxy encapsulated three-phase desgns are avalable to 0 hp. kva Capacty Eaton s motor drve solaton encapsulated and ventlated transformers are avalable n the same kva ratngs as general purpose encapsulated and ventlated transformers. Insulaton System and Temperature Rse Eaton s motor drve solaton ventlated transformers are manufactured usng a 0 C nsulaton system wth C temperature rse as standard. C or 0 C temperature rse are avalable as an opton. Encapsulated desgns use a 0 C nsulaton system wth C temperature rse as standard. 0 C temperature rse s avalable as an opton on encapsulated transformers. Frequency Most motor drve solaton transformers are desgned to operate n 0 Hz systems. /0 Hz desgns are avalable as an opton. Eaton s transformers can be desgned to operate at a varety of frequences. Wndng Materal Alumnum conductor and termnatons are provded as standard on ventlated transformers. Copper wndng conductors and termnatons are avalable as an opton. For encapsulated desgns, most models rated kva and below are constructed usng copper wndngs; kva and larger desgns have alumnum wndngs as standard, wth copper wndngs avalable as an opton. Installaton Clearances Eaton s ventlated transformers should be nstalled wth mnmum clearances as noted on the transformer s nameplate. Most Eaton transformers requre a mnmum of nches clearance behnd the transformer; however, many small kva ventlated transformers may be nstalled wth just nches clearance, whle large kva transformers requre nches or more of clearance behnd the transformer. Mnmum nstallaton clearances are stated on the nameplate of all transformers. The NEC requres a mnmum of nches clearance n front of the transformer. Care should be taken to avod restrctng the arflow through the bottom of the transformer. Transformers should be located n areas not accessble to the publc. Wrng Compartment Eaton s motor drve solaton transformers have wrng compartments szed to comply wth NEMA and NEC standards. Thermal Sensors Eaton s motor drve solaton transformers are provded wth thermal sensors mbedded n ther cols. The thermal sensors have normally open dry contacts that can be wred to provde a sgnal to remote locatons to ndcate a potental heatng problem wthn the transformer cols. Contacts are rated for 0 C. 0 0 CA0000E For more nformaton, vst:

22 .- Dstrbuton Dry-Type Transformers Hazardous Locaton Transformers Descrpton Aprl 0 Sheet 0 0 Hazardous Locaton Transformers Rated 00 V and Below Applcatons Eaton s hazardous locaton transformers are sutable for use n envronments classfed by the Natonal Electrcal Code (NEC) as Class I, Dvson, Groups A, B, C and D, as defned by NEC Artcle, when nstalled n complance wth NEC-recommended procedures for dry-type transformers rated 00 V and below. As defned by NEC Artcle 0, Class I, Dvson locatons nclude atmospheres that may contan volatle or gntable concentratons of flammable lquds or gas vapors, or locatons adjacent to such envronments. Acetone, ammona, benzene, gasolne, methane, propane and natural gas are examples of such substances. Eaton s hazardous locaton transformers are of the encapsulated desgn, and are avalable up to 00 V ratngs. Sngle-phase ratngs 0.0. kva; three-phase ratngs to. kva. Hazardous locaton transformers use a 0 C nsulaton system wth C temperature rse. When provded n a grade 0 or stanless steel enclosure, Eaton s hazardous locaton transformers meet the corroson-resstance requrements of a NEMA RX enclosure ratng. Hazardous locaton transformers can be mounted n any poston ndoors, and only n uprght postons for outdoor nstallatons. NEMA X rated enclosures manufactured usng ether grade 0 or stanless steel are avalable as an opton. Encapsulated transformers, ncludng Class I Dvson transformers, are outsde the scope of 0 CFR Part energy effcency requrements. Techncal Data Avalable Ratngs Eaton s hazardous locaton transformers are avalable n the same ratngs as sand and resn encapsulated transformers. Hazardous locaton transformers are avalable n a wde range of ratngs to meet specfc customer requrements. kva Capacty Sngle-phase desgns are avalable n ratngs from 0.0 kva through. kva; three-phase ratngs. kva. Insulaton System and Temperature Rse Eaton s hazardous locaton transformers are manufactured usng a 0 C nsulaton system wth C temperature rse as standard. 0 C temperature rse s avalable as an opton. Frequency Most hazardous locaton transformers are desgned to operate n 0 Hz systems. /0 Hz desgns are avalable as an opton. Eaton s transformers can be desgned to operate at a varety of frequences. Wndng Materal Copper conductors and termnatons are provded as standard on Eaton s hazardous locaton transformers rated kva and less. Alumnum conductor and termnatons are provded as standard on hazardous locaton transformers rated kva and greater. Copper wndng conductors and termnatons are avalable as an opton. Installaton Clearances Eaton s wall-mounted hazardous locaton transformers have a specally desgned hanger bracket that spaces the transformer an adequate dstance from the mountng surface. Transformers should be located n areas not accessble to the publc. 0 For more nformaton, vst: CA0000E

23 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Mn-Power Centers Descrpton.- Mn Power Centers Rated 00 V and Below Applcatons An Eaton mn power center replaces three ndvdual components: Prmary man breaker Transformer Dstrbuton loadcenter...by combnng all three nto a sngle unt. All nterconnectng wrng s performed at the factory. Mn power centers are deally suted for applcatons where 0 V s requred at a remote locaton. Parkng lots, workbenches and temporary power on constructon stes are common applcatons for mn power centers. Avalable wth alumnum bus and plug-on branch breakers, or wth copper bus and bolt-on branch breakers. Mn power centers ncorporate an encapsulated transformer n ther constructon. Prmary man breakers are avalable n a varety of nterruptng ratngs. When provded n a grade stanless steel enclosure, the Eaton mn power center meets the corrosonresstance requrements of a NEMA RX enclosure ratng. Mn power centers should be mounted n uprght postons only for all nstallatons. Mn power centers are outsde the scope of energy effcency mandates, ncludng 0 CFR Part. Techncal Data Avalable Ratngs Eaton s mn power centers are avalable n sngle-phase and threephase ratngs to 00 V, 00 A and 0 kva wth secondary loadcenters wth provsons for up to sngle-pole branch breakers. Mn power centers are avalable n a wde range of ratngs to meet specfc voltage converson requrements. kva Capacty Sngle-phase desgns are avalable n ratngs from kva through kva; three-phase ratngs kva through 0 kva. Insulaton System and Temperature Rse Mn power centers are manufactured usng a 0 C nsulaton system wth C temperature rse as standard. 0 C temperature rse s avalable as an opton. Frequency Most mn power centers are desgned to operate n 0 Hz systems. /0 Hz desgns are avalable as an opton. Eaton s mn power centers can be desgned to operate at a varety of frequences. Wndng Materal Alumnum conductor and termnatons are provded as standard on encapsulated transformers rated kva and greater. Copper wndng conductors and termnatons are avalable as an opton. Copper wndngs are standard n the all-copper model. Installaton Clearances Eaton s mn power centers are desgned to be wall-mounted. They have a specally desgned hanger bracket that spaces the mn power center an adequate dstance from the mountng surface. Mn power centers should be located n areas not accessble to the publc. Wrng Compartments Eaton s mn power centers have wrng compartments szed to comply wth NEMA and NEC standards. Ample condut knockouts are provded to offer ready access. The wrng compartment of wall-mounted transformers s located n the bottom porton of the enclosure. Prmary Man Breakers Mn power centers are provded wth prmary man crcut breakers that have an nterruptng ratng of kaic. EHD prmary man crcut breakers are provded as standard on mn power centers wth a 0 V prmary; 00 V desgns have an FD prmary man breaker as standard. Prmary man crcut breakers wth greater AIC ratngs are avalable as an opton on mn power centers wth plug-on secondary crcut breakers. Optonal prmary man breakers are FD (rate kaic at 0 V; kaic at 00 V), HFD ( kaic at 0 V; kaic at 00 V) or FDC (00 kaic at 0 V; kaic at 00 V). Branch Crcut Breakers Eaton s mn power centers are avalable wth an alumnum bus loadcenter nteror that accepts -nch plug-on branch crcut breakers Type BR famly. The all-copper mn power center s constructed wth a copper-wound transformer and a copper bus loadcenter nteror that accepts -nch bolt-on branch breakers Type BAB famly. 0 0 CA0000E For more nformaton, vst:

24 .- Dstrbuton Dry-Type Transformers Sngle-Phase Transformers for Motors Techncal Data Aprl 0 Sheet Transformer Selecton How to Select Sngle-Phase Unts. Determne the prmary (source) voltagethe voltage presently avalable.. Determne the secondary (load) voltagethe voltage needed at the load.. Determne the kva load: If the load s defned n kva, a transformer can be selected from the tabulated data. If the load ratng s gven n amperes, determne the load kva from the followng chart. To determne kva when volts and amperes are known, use the formula: kva = Volts x Amperes 000 If the load s an AC motor, determne the mnmum transformer kva from Table.-0 at the rght. Select a transformer ratng equal to or greater than the load kva.. Defne tap arrangements needed.. Defne temperature rse. Table.-0. Sngle-Phase AC Motors Note: When motor servce factor s greater than, ncrease full load amperes proportonally. Example: If servce factor s., ncrease ampere values by %. Horsepower Full Load Amperes Mnmum Volts 0 Volts 0 Volts 0 Volts Transformer kva / / / / / -/ -/ If motors are started more than once per hour, ncrease mnmum transformer kva by 0%. Table.-. Full Load Current n AmperesSngle-Phase Crcuts kva Voltage Table of standard transformer ratngs used to power sngle-phase motors n Table For more nformaton, vst: CA0000E

25 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Three-Phase Transformers for Motors Techncal Data.- Three-Phase Transformers How to Select Three-Phase Unts. Determne the prmary (source) voltagethe voltage presently avalable.. Determne the secondary (load) voltagethe voltage needed at the load.. Determne the kva load: If the load s defned n kva, a transformer can be selected from the tabulated data. If the load ratng s gven n amperes, determne the load kva from the followng chart. To determne kva when volts and amperes are known, use the formula: kva = Volts x Amperes x. 000 If the load s an AC motor, determne the mnmum transformer kva from Table.- at the rght. Select a transformer ratng equal to or greater than the load kva.. Defne tap arrangements needed.. Defne temperature rse. Usng the above procedure, select the transformer from the lstngs n ths catalog. Table.-. Three-Phase AC Motors Horsepower Full Load Amperes Mnmum 0 Volts 0 Volts 0 Volts 0 Volts Volts Transformer kva / / -/ -/ If motors are started more than once per hour, ncrease mnmum transformer kva by 0%. Note: When motor servce factor s greater than, ncrease full load amperes proportonally. Example: If servce factor s., ncrease above ampere values by %. Table.-. Full Load Current n AmperesThree-Phase Crcuts kva Voltage CA0000E For more nformaton, vst:

26 .-0 Dstrbuton Dry-Type Transformers Techncal Data Aprl 0 Sheet 0 0 Table.-. Typcal Data for Encapsulated 0 V Class General-Purpose Dry-Type Transformers, Alumnum Wound kva Frame Weght Lbs Losses n Watts Effcency % Regulaton % Impedance Sound Al Cu No Total / / / Full 00% 0% Mn. Max. Level db Load Load Load Load Load P.F. P.F. Type EP C Rse Sngle-Phase FR FR FR FR FRP FRP FRAP FRP FRP FRP FR FR FR FR FR0 FR FR00A Type EPT C Rse Three-Phase 0 FR0 FR00 FR0 FR FR FR FR Typcal values for alumnum wndngs. Refer to Pages.-.- for typcal data for copper wndngs. Up-to-date desgn data s avalable at Actual mpedance may vary ±.%. Type EPT transformers kva are T-T connected. Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson For more nformaton, vst: CA0000E

27 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Techncal Data.- Table.-. Typcal Data for 0 V Class DOE 0 Effcent Dry-Type Transformers, Alumnum Wound kva Frame Weght Losses n Watts Effcency (T Rse +0º) % Regulaton % Imp. X R Sound No Total at % % % Full 00% 0% T Rse T Rse T Rse Level db Load Rse +0 Load PF PF (per NEMA ST-0) Type DS- C Rse DOE 0 Effcent Sngle-Phase Type DS- C Rse DOE 0 Effcent Sngle-Phase Type DS- 0 C Rse DOE 0 Effcent Sngle-Phase Type DS- C Rse DOE 0 Effcent Type DT- C Rse DOE 0 Effcent Type DT- 0 C Rse DOE 0 Effcent Effcency at % Load ºC Inrush Absolute Max. Typcal values for alumnum wndngs. Refer to Pages.-.- for typcal data for copper wndngs. Up-to-date desgn data s avalable at Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson Practcal Max CA0000E For more nformaton, vst:

28 .- Dstrbuton Dry-Type Transformers Techncal Data Aprl 0 Sheet 0 0 Table.-. Typcal Data for 0 V Class K-Factor Rated DOE 0 Effcent Dry-Type Transformers, Alumnum Wound kva Frame Weght Losses n Watts Effcency (T Rse +0º) % Regulaton % Imp. X R No Total at % % % Full 00% 0% T Rse T Rse T Rse Load Rse +0 Load PF PF Type KT- K-Factor, C Rse DOE 0 Effcent Type KT- K-Factor, C Rse DOE 0 Effcent Type KT- K-Factor, 0 C Rse DOE 0 Effcent Type KT- K-Factor, C Rse DOE 0 Effcent Type KT- K-Factor, C Rse DOE 0 Effcent Type KT- K-Factor, 0 C Rse DOE 0 Effcent Sound Level db (per NEMA ST-0) Effcency at % Load ºC Inrush Absolute Max. Typcal values for alumnum wndngs. Refer to Pages.-.- for typcal data for copper wndngs. Up-to-date desgn data s avalable at Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson Practcal Max For more nformaton, vst: CA0000E

29 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Techncal Data.- Table.-. Typcal Data for 0 V Class DOE 0 Effcent Dry-Type Transformers, Copper Wound kva Frame Weght Losses n Watts Effcency (Trse +0 ) % Regulaton % X R Sound No Total at % % % Full 00% 0% Imp. Level db Load Rse +0 Load PF PF Type DS- C Rse DOE 0 Effcent Sngle-Phase Type DS- C Rse DOE 0 Effcent Sngle-Phase Type DS- 0 C Rse DOE 0 Effcent Sngle-Phase Type DT- C Rse DOE 0 Effcent Type DT- C Rse DOE 0 Effcent Type DT- 0 C Rse DOE 0 Effcent TP Effcency Inrush Absolute Max. Typcal values for copper wndngs. Refer to Pages.-0.- for typcal data for alumnum wndngs. Up-to-date desgn data s avalable at Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson Practcal Max CA0000E For more nformaton, vst:

30 .- Dstrbuton Dry-Type Transformers Techncal Data Aprl 0 Sheet 00 0 Table.-. Typcal Data for 0 V Class K-Factor Rated DOE 0 Effcent Dry-Type Transformers, Copper Wound kva Frame Weght Losses n Watts Effcency (Trse +0 ) % Regulaton % X R Sound TP No Total at % % % Full 00% 0% Imp. Level db Effcency Load Rse +0 Load PF PF Type KT- K-Factor, C Rse DOE 0 Effcent Type KT- K-Factor, C Rse DOE 0 Effcent Type KT- K-Factor, 0 C Rse DOE 0 Effcent Type KT- K-Factor, C Rse DOE 0 Effcent Type KT- K-Factor, C Rse DOE 0 Effcent Type KT- K-Factor, 0 C Rse DOE 0 Effcent Inrush Absolute Max. Typcal values for copper wndngs. Refer to Pages.-0.- for typcal data for alumnum wndngs. Up-to-date desgn data s avalable at Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson Practcal Max For more nformaton, vst: CA0000E

31 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Techncal Data.- Table.-. Typcal Data for 0 V Class NEMA TP- Dry-Type Transformers, Alumnum Wound kva Frame Weght Losses n Watts Effcency (T Rse +0º) % Regulaton % Imp. X R No Total at % % % Full 00% 0% T Rse T Rse T Rse Load Rse +0 Load PF PF Type DS- C Rse NEMA TP- Effcent Sngle-Phase Type DS- C Rse NEMA TP- Effcent Sngle-Phase Type DS- 0 C Rse NEMA TP- Effcent Sngle-Phase Type DT- C Rse NEMA TP- Effcent D D D D D D A A A , Type DT- C Rse NEMA TP- Effcent D D D D D A A A Type DT- 0 C Rse NEMA TP- Effcent D D D A A Sound Level db TP Effcency Inrush Absolute Max. Typcal values for alumnum wndngs. Refer to Pages.-.- for typcal data for copper wndngs. Up-to-date desgn data s avalable at Actual mpedance may vary ±.%. Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson Practcal Max CA0000E For more nformaton, vst:

32 .- Dstrbuton Dry-Type Transformers Techncal Data Aprl 0 Sheet Table.-0. Typcal Data for 0 V Class K-Rated, TP- Dry-Type Transformers, Alumnum Wound kva Frame Weght Losses n Watts Effcency (T Rse +0º) % Regulaton % Imp. X R No Total at % % % Full 00% 0% T Rse T Rse T Rse Load Rse +0 Load PF PF Type KT- C Rse NEMA TP- Effcent D D D D A A A Type KT- C Rse NEMA TP- Effcent D D D D A A Type KT- 0 C Rse NEMA TP- Effcent D D D A A Type KT- C Rse NEMA TP- Effcent D D D A A Type KT- C Rse NEMA TP- Effcent D D D A A A Type KT- 0 C Rse NEMA TP- Effcent D D D A A Sound Level db TP Effcency Inrush Absolute Max. Typcal values for alumnum wndngs. Refer to Pages.-.- for typcal data for copper wndngs. Up-to-date desgn data s avalable at Actual mpedance may vary ±.%. Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson Practcal Max For more nformaton, vst: CA0000E

33 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Techncal Data.- X R Sound Table.-. Typcal Data for 0 V Class NEMA TP- Dry-Type Transformers, Copper Wound kva Frame Weght Losses n Watts Effcency (Trse +0 ) % Regulaton % No Total at % % % Full 00% 0% Imp. Level db Load Rse +0 Load PF PF Type DS- C Rse NEMA TP- Effcent Sngle-Phase Type DS- C Rse NEMA TP- Effcent Sngle-Phase Type DS- 0 C Rse NEMA TP- Effcent Sngle-Phase Type DT- C Rse NEMA TP- Effcent D D D D D D A A Type DT- C Rse NEMA TP- Effcent D D D D D A A Type DT- 0 C Rse NEMA TP- Effcent D D D A A TP Effcency Inrush Absolute Max. Typcal values for copper wndngs. Refer to Pages.-0.- for typcal data for alumnum wndngs. Up-to-date desgn data s avalable at Actual mpedance may vary ±.%. Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson Practcal Max CA0000E For more nformaton, vst:

34 .- Dstrbuton Dry-Type Transformers Techncal Data Aprl 0 Sheet 0 0 X R Sound Table.-. Typcal Data for 0 V Class K-Rated, TP- Dry-Type Transformers, Copper Wound kva Frame Weght Losses n Watts Effcency (Trse +0 ) % Regulaton % No Total at % % % Full 00% 0% Imp. Level db Load Rse +0 Load PF PF Type KT- C Rse NEMA TP- Effcent D D D D A A Type KT- C Rse NEMA TP- Effcent D D D D A A Type KT- 0 C Rse NEMA TP- Effcent 0. D D D A A Type KT- C Rse NEMA TP- Effcent 0. D D D A A Type KT- C Rse NEMA TP- Effcent 0. D D D A A Type KT- 0 C Rse NEMA TP- Effcent 0. D D D A A A TP Effcency Inrush Absolute Max. Typcal values for copper wndngs. Refer to Pages.-0.- for typcal data for alumnum wndngs. Up-to-date desgn data s avalable at Actual mpedance may vary ±.%. Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson Practcal Max For more nformaton, vst: CA0000E

35 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Techncal Data.- X R Sound Table.-. Typcal Data for 0 V Class K-Rated and HMT, TP- and CSL- Dry-Type Transformers, Copper Wound kva Frame Weght Losses n Watts Effcency (Trse +0 ) % Regulaton % Effcency No Total at % % % Full 00% 0% Imp. Level db Load Rse +0 Load PF PF Type KT- C Rse CSL- Effcent D D D D A Type KT- C Rse CSL- Effcent 0. D D D D A Type NON HMT C Rse NEMA TP- Effcent D D D A A X X Type THR HMT C Rse NEMA TP- Effcent D D D A A X X Inrush Absolute Max. Typcal values for copper wndngs. Refer to Pages.-0.- for typcal data for alumnum wndngs. Up-to-date desgn data s avalable at Actual mpedance may vary ±.%. Note: Performance data s based upon 0 V delta prmary and a 0Y/0 V secondary for three-phase transformers; 0 x 0 V prmary and a 0/0 V secondary for sngle-phase transformers. Refer to Eaton for kv class nformaton. All data s subject to future revson Practcal Max CA0000E For more nformaton, vst:

36 .-0 Dstrbuton Dry-Type Transformers Dmensons Aprl 0 Sheet 0 DmensonsVentlated Transformers Wdth Top Wdth Top Heght Left Front Wdth Top Front Length Drawng Heght Left Front Heght Left 0 Length Drawng Length Drawng Fgure.-. Enclosure Dmensonal DrawngsVentlated Transformers Table.-. Ventlated TransformersApproxmate Dmensons n Inches (mm) Frame Drawng Dmensons Number Heght Wdth Length FR FR FR FR0 FR, FRE FR FRB, FRD FRD FRD FRA FR FRA FR FR, FRE, FRX FR0, FR0E, FR0X FR.0 (.0). (.).0 (0.).0 (0.). (). () 0.00 (.0).00 (0.).00 (0.). (.). (.). (.). (.).00 (0.0).00 (0.0) 0.00 (.0) (.) (.). (.). (.). (.). (.).00 (.).00 (.).00 (.). (.). (). (). ().0 (.).0 (.). (.). (.) 0. (.0. (0.). (0.). (). (). (.).00 (.).00 (.). (.). (.) 0. (.). (.). (0.). (0.). (0.) 0 For more nformaton, vst: CA0000E

37 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Dmensons.- Wdth Top Heght Left Front Length Drawng Fgure.-. Enclosure Dmensonal DrawngsVentlated Transformers Table.-. Ventlated TransformersApproxmate Dmensons n Inches (mm) Frame Drawng Dmensons Number Heght Wdth Length 0.00 (.). (.0).00 (0.). (.) 0.00 (.0) 0.00 (.0). (.). (.) 0. (.). (.0).00 (.).00 (.0). (0.). (.).00 (0.). (00.0). (.).00 (.) 0 0 CA0000E For more nformaton, vst:

38 .- Dstrbuton Dry-Type Transformers DmensonsEncapsulated Aprl 0 Sheet 0 Length Wdth Top Rght Back Heght Length Wdth Top Rght Back Heght Length Wdth Rght Top Back Heght Drawng Drawng Drawng Wdth 0 Length Wdth Rght Top Drawng Back Heght Length Rght Fgure.-. Enclosure Dmensonal DrawngsEncapsulated Transformers Top Drawng 0 Back Heght Length Wdth Rght Top Back Drawng Heght Table.-. Encapsulated TransformersApproxmate Dmensons n Inches (mm) Frame Drawng Dmensons Number Heght Wdth Length FR FR FR FR FR FRA FRA FR FR FR FR FR0 FR FR0 FR0 FR FR0 FR FR (.). (.). (.). (.). (.). (.). (.). (0.). (0.). ().00 (0.). (.).00 (0.). (.). (.).00 (.).00 (.). (.). (.). (0.). (0.). (0.). (.). (.). (.). (.). (.). (.). (.) 0. (.). () 0. (.). (). (.). (.). (.). (.). (.).00 (0.).00 (0.).00 (0.).0 (0.). (.). (.). (.). (.). (.).00 (0.). (.). (.). (.). (.). (.) 0. (.) 0. (.). (.). (.) 0 For more nformaton, vst: CA0000E

39 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers DmensonsEncapsulated.- Wdth Top Length Wdth Left Top Front Heght Length Left Drawng Front Heght Length Wdth Rght Top Back Heght Drawng Fgure.-. Enclosure Dmensonal DrawngsEncapsulated Transformers Table.-. Encapsulated TransformersApproxmate Dmensons n Inches (mm) Frame Drawng Dmensons Number Heght Wdth Length Drawng 0 FR FR00A FRP FRAP FRP FRP 0. (.0). (.). (.). (.).0 (0.). (.0).0 (.) (.). (.0). (.). (.). (.0). (.).0 (.). (.). (.). (.). (0.) 0 CA0000E For more nformaton, vst:

40 .- Dstrbuton Dry-Type Transformers DmensonsEncapsulated Aprl 0 Sheet 00 Wdth Length Top Wdth Top Top Heght Left Front Left Front Heght Left Front Heght 0 0 Length Drawng Drawng Drawng Fgure.-. Enclosure Dmensonal DrawngsEncapsulated Transformers Table.-. Encapsulated TransformersApproxmate Dmensons n Inches (mm) Frame Drawng Dmensons Number Heght Wdth Length FR0 FR0 FR0 FR00 FR FR FR FR FR FR.0 (0.). (.).0 (0.).0 (0.). (.). (.). (.). (.). (.0).0 (.). (0.. (.). (0.0). (0.0). (.) 0.00 (.0) 0.00 (.0). (.). (.) 0. (.). (0.).0 (0.) 0.0 (.) 0.0 (.). (.) 0. (.) 0. (.). (.). (). () Length Wdth For more nformaton, vst: CA0000E

41 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers Dmensons.- Wdth Heght Length Wdth Left Top Drawng Front Heght Wdth Left Top Front Heght Left Top Front Fgure.-0. Enclosure Dmensonal DrawngsTotally Enclosed Nonventlated Transformers Table.-. Totally Enclosed Nonventlated Transformers Approxmate Dmensons n Inches (mm) Frame Drawng Dmensons Number Heght Wdth Length FRN FRN FR0N FRN FRBN, FRDN FRDN FRDN FRAN FRN FRAN FRN FRN FR0N Length. (.).0 (0.).0 (0.). () 0.00 (.0). (.). (.). (.). (.0). (.). (0.).00 (0.0).00 (0.0) Drawng (.). (.). (.). (.).00 (.).00 (.).00 (.). (.). (). (). (). (.). (.) See Eaton Catalog CA00000E, Electrcal Sector Solutons Volume Commercal Dstrbuton, Tab for product nformaton and frame cross-reference data. 0. (.). (0.). (0.). (). (.).00 (.).00 (.). (.). (.) 0. (.). (.). (0.). (0.) Length Drawng 0 0 CA0000E For more nformaton, vst:

42 .- Dstrbuton Dry-Type Transformers FAQ Product Selecton Aprl 0 Sheet Frequently Asked Questons About Transformers Can 0 Hz transformers be used at other frequences? Transformers rated for 0 Hz can be appled to crcuts wth a hgher frequency, as long as the nameplate voltages are not exceeded. The hgher the frequency that you apply to a 0 Hz transformer, the less voltage regulaton you wll have. 0 Hz transformers may be used at lower frequences, but only at reduced voltages correspondng to the reducton n frequency. For example, a 0 0 V 0 Hz transformer can carry rated kva at Hz but only when appled as a V transformer (/0 x 0 = 00). Can sngle-phase transformers be used on a three-phase source? Yes. Any sngle-phase transformer can be used on a threephase source by connectng the prmary termnals of the sngle-phase transformer to any two wres of a three-phase system. It does not matter whether the three-phase source s three-phase three-wre or three-phase four-wre. The output of the transformer wll be sngle-phase. Can transformers be used to create three-phase power from a sngle-phase system? No. Sngle-phase transformers alone cannot be used to create the phase-shfts requred for a three-phase system. Phase-shftng devces (reactors or capactors) or phase converters n conjuncton wth transformers are requred to change sngle-phase power to three-phase. What consderatons need to be taken nto account when operatng transformers at hgh alttudes? At alttudes greater than 00 ft (000 m), the densty of the ar s lesser than at lower elevatons. Ths reduces the ablty of the ar surroundng a transformer to cool t, so the temperature rse of the transformer s ncreased. Therefore, when a transformer s beng nstalled at alttudes greater than 00 ft (000 m) above sea level, t s necessary to derate the nameplate kva by 0.% for each 0 ft (00 m) n excess of 00 feet. What consderatons need to be taken nto account when operatng transformers where the ambent temperature s hgh? Eaton s dry-type transformers are desgned n accordance wth ANSI standards to operate n areas where the average maxmum ambent temperature s 0 C. For operaton n ambent temperatures above 0 C, there are two optons:. Order a custom-desgned transformer made for the specfc applcaton.. Derate the nameplate kva of a standard transformer by % for each 0 C of ambent above 0 C. What s the normal lfe expectancy of a transformer? When a transformer s operated under ANSI/IEEE basc loadng condtons (ANSI C.), the normal lfe expectancy of a transformer s 0 years. The ANSI/IEEE basc loadng condtons are: A. The transformer s contnuously loaded at rated kva and rated voltages. B. The average temperature of the ambent ar durng any -hour perod s equal to 0 C and at no tme exceeds 0 C. C. The alttude where the transformer s nstalled does not exceed 00 ft (000 m). What are Insulaton Classes? Insulaton classes were orgnally used to dstngush nsulatng materals operatng at dfferent temperatures. In the past, letters were used for the dfferent desgnatons. Recently, nsulaton system temperatures ( C) have replaced the letters desgnatons. Table.-0. Insulaton Classes Prevous Desgnaton Class A 0 Class B Class F 0 Class H 0 Class R 0 Insulaton System Ratng ( C) How do you know f the enclosure temperature s too hot? UL and CSA standards strctly regulate the hghest temperature that an enclosure can reach. For ventlated transformers, the temperature of the enclosure should not ncrease by more than C n C ambent at full rated current. For encapsulated transformers, the temperature of the enclosure should not ncrease by more than C n a C ambent at full rated current. Ths means that t s permssble for the temperature of the enclosure to reach 0 C ( F). Although ths temperature s very warm to the touch, t s wthn the allowed standards. A thermometer should be used to measure enclosure temperatures, not your hand. Can transformers be reverse-connected (reverse-fed)? Yes, wth lmtatons. Eaton s sngle-phase transformers rated kva and larger can be reverse-connected wthout any loss of kva capacty or any adverse effects. Transformers rated kva and below, because there s a turns rato compensaton on the low voltage wndng that adjusts voltage between no load and full load condtons, should not be reverse-fed. Three-phase transformers wth ether delta-delta or delta-wye confguratons can also be reverse-connected for step-up operaton. When reverse-feedng a delta-wye connected transformer, there are two mportant consderatons to take nto account: () The neutral s not connected, only the three-phase wres of the wye system are connected; and () the ground strap between X0 and the enclosure must be removed. Due to hgh nrush currents that may be created n these applcatons, t s recommended that you do not reverse-feed transformers rated more than kva. The preferred soluton s to purchase an Eaton step-up transformer desgned specfcally for your applcaton. Can transformers be connected n parallel? Yes, wth certan restrctons. For sngle-phase transformers beng connected n parallel, the voltages and mpedances of the transformers must be equal (mpedances must be wthn.% of each other). For three-phase transformers, the same restrctons apply as for sngle-phase transformers, plus the phase shft of the transformers must be the same. For example, a delta-wye connected transformer (0 phase shft) must be connected n parallel wth another delta-wye connected transformer, not a delta-delta connected transformer (0 phase shft). For more nformaton, vst: CA0000E

43 Aprl 0 Sheet 0 Dstrbuton Dry-Type Transformers FAQ Product Selecton.- Why s the mpedance of a transformer mportant? The mpedance of a transformer s mportant because t s used to determne the nterruptng ratng and trp ratng of the crcut protecton devces on the load sde of the transformer. To calculate the maxmum short-crcut current on the load sde of a transformer, use the followng formula: Maxmum Short-Crcut Load Current (Amps) Full Load Current (Amps) Transformer Impedance Full load current for sngle-phase crcuts s: Nameplate Volt-Amps Load (output) Voltage and for three-phase crcuts the full load current s: Nameplate Volt-Amps Load (output) Volts Example: For a standard three-phase, kva transformer, rated 0 V delta prmary and 0Y/0 V secondary (catalog number VMTJ) and mpedance equal to.%, the full load current s:,000 VA = 0. A 0 V x. The maxmum short-crcut load current s: 0.A = 0 A 0.0 = The crcut breaker or fuse on the secondary sde of ths transformer would have to have a mnmum nterruptng capacty of 0 A at 0 V. NEMA ST-0 (). A smlar transformer wth lower mpedance would requre a prmary crcut breaker or fuse wth a hgher nterruptng capacty. What clearances are requred around transformers when they are nstalled? All dry-type transformers depend upon the crculaton of ar for coolng; therefore, t s mportant that the flow of ar around a transformer not be mpeded. Many Eaton transformers requre a mnmum clearance of nches from panels wth ventlaton openngs. However, small kva DOE 0 effcent ventlated transformers are UL approved to be nstalled wth just nches clearance, whle large kva transformers requre nches or more clearance. In complance wth NEC 0., Eaton s ventlated transformers have a note on ther nameplates dentfyng the mnmum requred clearance from the ventlaton openngs and walls or other obstructons. Ths clearance only addresses the ventlaton needs of the transformer. There may be addtonal local codes and standards that affect nstallaton clearances. Transformers should not be mounted n such a manner that one unt wll contrbute to the addtonal heatng of another unt, beyond allowable temperature lmts, for example, where two unts are mounted on a wall one above the other. How Can I Reduce Transformer Sound Levels? All transformers emt some audble sound due manly to the vbraton generated n ther core by alternatng flux. NEMA ST-0 (0) defnes the maxmum average sound levels for transformers. Table.-. NEMA ST-0 (0) Maxmum Audble Sound Levels for 00 V Class Transformers (dba) Equvalent Wndng kva Range.00 and below.0 to.00.0 to.00.0 to to.00.0 to.00.0 to.. to.00.0 to.00.0 to to to to Average Sound Level, Decbels Self-Cooled Ventlated A B C D K Factor = K Factor = K Factor = K Factor = K Factor = Forced Ar When Fans Runnng Greater than 000 Consult factory Note: Consult factory for nonlnear requrements exceedng a K-factor ratng of 0. When the fans are not runnng, columns A and B apply. Sound levels are measured usng the A-weghted scale (dba). All Eaton transformers are desgned to have audble sound levels lower than those requred by NEMA ST-0 (0). However, consderaton should be gven to the specfc locaton of a transformer and ts nstallaton to mnmze the potental for sound transmsson to surroundng structures and sound reflecton. The followng nstallaton methods should be consdered:. If possble, mount the transformer away from corners of walls or celngs. For nstallatons that must be near a corner, use sound-absorbng materals on the walls and celng f necessary to elmnate reflecton.. Provde a sold foundaton for mountng the transformer and use vbraton dampenng mounts f not already provded n the transformer. Eaton s ventlated transformers contan a bult-n vbraton dampenng system to mnmze and solate sound transmsson. However, supplemental vbraton dampenng mounts nstalled between the floor and the transformer may provde addtonal sound dampenng.. Make electrcal connectons to the transformer usng flexble condut.. Locate the transformer n an area where audble sound s not offensve to buldng nhabtants.. Install low sound transformers (up to db below NEMA ST-0 [0] sound lmts). Self- Cooled Sealed 0 0 CA0000E For more nformaton, vst:

44 .- Dstrbuton Dry-Type Transformers Aprl 0 Sheet Ths page ntentonally left blank. For more nformaton, vst: CA0000E