Glossary - Power Definitions

Educationa Gossary - Power Definitions Basic & Sateite Switched Software Environmenta Accessories Brackets Resources Educationa What is an Amp? An Amp (or Ampere) is the standard measure of eectrica current. Much ike water fowing through a pipe, the Amp is a measure of how much eectricity is moving through a wire at a given time. The Amp draw of a circuit is dependent on the needs of the devices pugged into it, and is imited by the branch circuit protection. What is a Vot? A Vot is the standard measure of eectrica potentia and a fixed vaue for every circuit. Votage is measured with respect to a reference point (usuay between the two respective conductors of the circuit). Votage is anaogous to pressure in a water pipe. Higher pressures, or higher votages, aow more energy to fow within a given amount of time for a given wire size. Standard votages present in most data centers are 120V and 208V in the U.S., and 230V in continenta Europe. Some newer U.S. data centers are being designed to utiize 230V. What is a Watt? A Watt is the measure of tota work performed by the energy consumed in a system. The cacuation is: Watts = Vots x Amps x Power Factor. What is a Energy? Energy is eectricty as a raw materia, measured in Vots and Amps avaiabe to do work. What is AC? Aternating Curent, or AC, is energy deivered in a form that can trave the ong distances necessary from generating pants to homes and businesses. The term AC refects the fact that the votage and current are aways changing in vaue, or aternating between a positive and negative threshod over a centerine. What is DC? Direct Current, or DC, is energy that does not aternate over a fixed period of time, but rather has a steady vaue with reference to zero. DC does not trave great distances we. What does RMS mean? RMS stands for Root-Mean-Squared. It is used in conjunction with AC Vots and AC Amps to express an average vaue. A true RMS cacuation takes into account the shape and phases of the wave forms being deivered to a circuit. AC votage and current are ever-changing vaues. Using RMS measurements provides usefu vaues. Additiona power charts and cacuations avaiabe on page 180. What is Apparent Power? Apparent Power is the instantaneous cacuation of Vots x Amps. What is Rea Power? Rea Power is the RMS vaue of Watts. What is Power Factor? Power Factor is the ratio of Rea Power to Apparent Power. Its vaue ranges from 0 to 1. A vaue of 1, or 100% is unity power. Lower vaues of Power Factor indicate that the circuit is wasting energy. Any difference between the RMS vaue of Watts and the Vot-Amps vaue indicates inefficiencies in the way power is being used by the equipment on the circuit. What is PUE? PUE stands for Power Use Effectiveness. PUE is a measure of how efficienty power is being used in a data center, and is becoming the standard benchmarking metric in most data centers. PUE is determined by dividing the tota faciity power use (Buiding Watts) by the IT equipment oad (IT Watts). The power distribution within the buiding has severa points where osses occur (UPS, transformers, wire runs), so the idea pace to measure the IT power oad is at the cabinet eve within the power strip. These readings can be coected and aggregated to determine the IT power oad. Once an initia assessment of PUE has been made, efforts can be made to improve PUE by appying various methods to improve operationa efficiencies in the data center. What is EUE? Unike the commony used Power Usage Effectiveness metric, EUE is based on energy rather than power. The EPA Energy Star program focuses measurements on energy rather than power. The new Energy Star certification is a rating for data centers and is based on Energy Usage Effectiveness (EUE). A data center s EUE, normaized for a variety of the faciity s characteristics, cacuates the 1-100 rating for that faciity. Data centers in the top 25 percentie quaify for Energy Star certification. EUE is cacuated by dividing the tota source energy (ITVA) by tota UPS energy (UPS VA). Some factors wi not be a part of the cacuation, such as heating and cooing degree days, data center type (traditiona, hosting, Internet, etc) and UPS utiization. The EPA pans to aunch the new rating system in Apri of 2010. What is DCiE? DCiE stands for Data Center Infrastructure Efficiency. DCIE is IT Power divided by Tota Faciity Power, expressed as a percent (%). DCIE is the inverse of PUE. = = = Buiding Watts IT Watts IT VA UPS VA IT Watts Buiding Watts 176

Educationa Gossary - Power Definitions Three Phase Load Cacuator Geist has generated a usefu too for cacuating phase oads in deta or wye configured three phase power distribution units. This too, ocated in the Literature Sheets section of the Geist website, aows users to input known oad vaues to determine resuting ine currents. This is particuary usefu in understanding 20-60 amp three phase units incorporating mutipe interna circuits. Basic & What is 3 Phase DELTA? 3 Phase DELTA from 208V Source What is 3 Phase WYE? 3 Phase WYE from 120/208V Source GROUND L15-20P Pug A 3 Phase DELTA is a 4 wire configuration consisting of 3 phase conductors (X, Y and Z) and a Ground. Without the neutra present, ony phase to phase wiring is possibe. The potentia between any two phase conductors is typicay 208V. X PHASE Y PHASE Z PHASE 208V (XY) 208V (YZ) X PHASE Z PHASE 208V (ZX) Y PHASE NEUTRAL X PHASE Z PHASE GROUND Y PHASE L21-20P Pug A 3 Phase 120/208V WYE is a 5 wire configuration consisting of 3 Phase conductors (X, Y and Z), Neutra and Ground. The potentia between any 2 phase conductors is 208V. The potentia between any phase and neutra is 120V. This configuration can be wired to provide 120V, 208V or a combination of both votages within one PDU. X PHASE Y PHASE Z PHASE NEUTRAL 208V (XY) 208V (YZ) 208V (ZX) 120V (XN) 120V (YN) 120V (ZN) Switched Sateite Environmenta Software Accessories Brackets Educationa Resources GROUND GROUND 800-432-3219 177

Educationa Gossary - Power & Conformance Definitions Basic & Sateite Switched Software Environmenta Accessories Brackets Resources Educationa What is an IEC Connector? The Internationa Eectrotechnica Commission (IEC) is a not-for profit, non-governmenta internationa standard organization that pubishes Internationa Standards for eectrica and eectronic products. IEC connectors are inets and sockets used for AC Mains eectricity that conform to the IEC 60320 Standard (pugs fa under IEC 60309). The pug and receptace configuration chart on page 198 shows IEC configurations that are avaiabe in Geist products. What is a NEMA Connector? NEMA, which stands for the Nationa Eectrica Manufacturers Association, is a standards-setting body for the North American eectrica industry. NEMA connectors are pugs and receptaces used for mains eectricity that conform to NEMA standards. The pug and receptace configuration chart on page 198 shows NEMA configurations that are avaiabe in Geist products. What is AWG? American Wire Gauge standard measurement for the cross sectiona area of an eectica conductor. What is a Penum Rated cabe? A Penum is compartment or chamber used for HVAC air distribution. In the data center, this is typicay the space beow a raised foor. A Penum Rated cabe refers to structured cabing permitted by buiding code for use in penum spaces. Penum rated cabe has a sow-burning, fire-resistant casing that emits itte smoke. Artice 645 of the Nationa Eectric Code (NEC), tited Information Technoogy Equipment, discusses the use of power cabes under a raised foor. drawing courtesy of www.penaform.com What are Isoated Ground units? Soid state eectronic equipment contain microprocessors that are adversey affected by Eectromagnetic Interference (EMI). In Geist s Isoated Ground units, the receptace ground conductor is permitted to pass through pane boards, junction boxes, etc. without being bonded to the equipment grounding conductor. This isoation minimizes EMI potentia within the instaation. An externa chassis grounding wire is eectricay isoated from the receptace grounding wire. It must be connected to a reiabe earth connection to minimize the potentia for eectrica shock. Isoated Ground PDU s are especiay beneficia in audio/ video appications. More information on NEC s codes for isoated ground systems can be found in the NEC Section 250-146(d). Standard Geist Isoated Ground units can be found on pages 11 and 24. Contact Customer Service with your custom requirements. CAUTI: CHASSIS GROUND MUST BE CNECTED TO EARTH GROUND. CAUTI: UNIT CTAINS ISOLATED GROUND RECEPTACLES. CHASSIS GROUND MUST BE CNECTED TO EARTH GROUND BEFORE INSTALLING UNIT. What is the FCC? The FCC, or Federa Communications Commission, is a United States Government Agency charged with reguating interstate and internationa communications by radio, teevision, wire, sateite, and cabe. FCC rues prohibit eectronic equipment used in the United States from emitting any Eectromagnetic Interference (EMI) that endangers the functioning of a radio navigation service or other safety services or seriousy degrades, obstructs, or repeatedy interrupts a radio communications service. The FCC has estabished imum emission eves for unintentiona radiators based on whether they are intended for commercia or househod use. Products intended for househod use are required to meet Cass B imits, whie products intended for commercia use are required to meet Cass A imits. Representative sampes of Geist Manufacturing products are tested by an FCC Registered Lab to the Cass A imits. A Geist Manufacturing products are compiant with FCC reguations. 178

Educationa Gossary - Conformance Definitions What is UL? UL stands for Underwiters Laboratories, Inc. It is an independent agency approved by NFPA (Nationa Fire Protection Association) to determine the ife safety of equipment used in the workpace. What does UL Listed mean? The term is used by UL when it determines that a compete product, such as a persona computer power strip (PDU), is safe for use as intended by the manufacturer. Ony UL can authorize the use of the UL Listing Mark. What does the culus mark represent? This mark is paced on products that have been tested and evauated by UL to both Canadian and US safety requirements. What does the CE mark represent? The CE Mark is a required conformance mark that must be paced on certain types of eectrica and eectronic equipment sod in the European Union. The CE mark is used to indicate that a manufacturer certifies that a product conforms to a appicabe European safety and Eectromagnetic Compatibiity (EMC) directives. How Do I Decipher the Geist product abe? What is the NEC? NEC stands for Nationa Eectric Code and is sponsored by the NFPA. These guideines, aso known as NFPA70, are used to safeguard ife and property from hazards arising from eectricity. The NEC is not a US Law, however conformance to is is commony mandated by State or oca aw. UL is an independent agency approved by the NFPA to ensure product compiance with the NEC. Additiona information is avaiabe at www.nfpa.org. What is RoHS Compiance, and how does it affect me? RoHS (pronounced rows or row-hoss ) is an acronym for Restriction on the use of Certain Hazardous Substances. The term RoHS is most commony used to refer to the European Union s (EU) RoHS Directive. The objective of the EU RoHS directive is to restrict the use of hazardous substances in eectrica and eectronic equipment. This reduction is intended to both reduce the amount of hazardous substances in andfis resuting from the disposa of eectrica and eectronic equipment and to minimize the heath and environmenta impact of recycing eectrica and eectronic equipment. RoHS Compiance is mandatory for PDU products sod in Europe, and is becoming increasingy more important for PDU products sod in the United States. For exampe, Caifornia has aready passed Proposition 65, a RoHS-ike aw requiring certain eectrica and eectronic equipment to compy with the requirements estabished by the EU RoHS Directive. 1. The mode or type designation 2. The rated votage or votage range 3. The rated frequency or frequency range 4. The rated current or current range 5. The manufacturer s name or registered trademark or unique number assigned by testing agency 6. The approva mark of the safety agency that tested the product 7. UL fie # - more information avaiabe at htp://database.u.com/ 8. Safety agencies require documentation of the month and year a product is manufactured. Seria numbers are used by most manufacturers to accompish this. The seria numbers utiized on a daiy, weeky or monthy basis are recorded. Geist s seria numbers and barcodes enabe detaied tracking. Basic & Switched Sateite Environmenta Software Accessories Brackets Educationa Resources 2ZPRM128-106C19PS15 Made In USA 48 A, 208-240 VAC, 3~, 50/60 Hz 4 5 6 2 3 1 INFORMATI TECHNOLOGY EQUIPMENT E214832 7 No user serviceabe parts inside. Ne contient aucun composant pouvant etre repare par utiisateur. 8 GC09110418 800-432-3219 179

Educationa Charts Basic & Sateite Switched Software Environmenta Accessories Brackets Resources Educationa Ohm s Law Pie Chart Power Whee V x I P R PDU Namepate Current Rating R x I P V 2 V R 2 V R Branch Circuit Rating R x I P I 2 P I 2 V P P x R V I Power Ratings and Requirements for a Singe AC Feed Vots Namepate Vots Actua Deivered Phase Watts 80% Rue De-rated Watts Cabe AWG & Ratings - NEC / UL Requirements Branch Circuit Rating PDU Namepate Current x V PDU Namepate Rating BTU / hr (kw x 3414) AC Tons** (BTU / 12000) Air Voume*** (120 CFM * kw) 12 15 125 120 1 1,800 1,440 1.4 4,916 0.41 168 16 20 125 120 1 2,400 1,920 1.9 6,555 0.55 228 24 30 125 120 1 3,600 2,880 2.9 9,832 0.82 348 16 20 250 208 1 4,160 3,328 3.3 11,362 0.95 396 24 30 250 208 1 6,240 4,992 5.0 17,043 1.42 600 35 50 250 208 1 10,400 7,280 7.3 24,854 2.07 876 48 60 250 208 1 12,480 9,984 10.0 34,085 2.84 1,200 16 20 230 230 1 4,600 3,680 3.7 12,564 1.05 444 24 30 230 230 1 6,900 5,520 5.5 18,845 1.57 660 48 60 230 230 1 13,800 11,040 11.0 37,691 3.14 1,320 16 20 120/208 208 3 7,197 5,757 5.8 19,656 1.64 696 24 30 120/208 208 3 10,795 8,636 8.6 29,484 2.46 1,032 35 50 120/208 208 3 17,992 12,594 12.6 42,997 3.58 14,712 48 60 120/208 208 3 21,590 17,272 17.3 58,968 4.91 2,076 80 100 120/208 208 3 35,984 28,787 28.8 98,279 8.19 3,456 100 125 120/208 208 3 44,980 35,984 36.0 122,849 10.24 4,320 120 150 120/208 208 3 53,976 43,181 43.2 147,419 12.28 5,184 16 20 230/400 230 3 13,800 11,040 11.0 37,691 3.14 1,320 24 30 230/400 230 3 20,700 16,560 16.6 56,536 4.71 1,992 *3 Phase power is cacuated by mutipying singe phase by the sq-root of 3 or 1.73 **Tons of Air Conditioning required to remove heat from associated IT oad. ***The voume of air that is typicay required by the IT equipment for each kw of IT oad can typicay range from 80 to 140 CFM. Wire AWG # of Conductors 15 A, 120 V 12 A, 120 V 14 3 15 A, 208 V 12 A, 208 V 14 3 20 A, 120 V 16 A, 120 V 12 3 20 A, 208 V 16 A, 208 V 12 3 20 A, 208 V 3~ DELTA 16 A, 208 V 3~ DELTA 12 4 20 A, 120/208 V 3~ WYE 16 A, 120/208 V 3~ WYE 12 5 30 A, 120 V 24 A, 120 V 10 3 30 A, 208 V 24 A, 208 V 10 3 30 A, 208 V 3~ DELTA 24 A, 208 V 3~ DELTA 10 4 30 A, 120/208 V 3~ WYE 24 A, 120/208 V 3~ WYE 10 5 50 A, 208 V 3~ DELTA 35 A, 208 V 3~ DELTA 8 4 50 A, 208 V 40 A, 208 V 6 3 50 A, 208 V 3~ DELTA 40 A, 208 V 3~ 6 4 60 A, 208 V 48 A, 208 V 6 3 60 A, 208 V 3~ DELTA 48 A, 208 V 3~ DELTA 4 4 180

Educationa Charts 35A 3 Phase with 3 each 2 poe breakers 80A 3 Phase with 4 each 3 poe breakers Input Power: (50A) (208V) (1.73) (80%) = 14.4kW 50A breaker at pane unit de-rated to 40A per NEC oad is imited by breaker oads 50 Lxy - 20A Input Power: (100A) (208V) (1.73) (80%) = 28.8kW 60 100A breaker at pane unit de-rated to 80A per UL / NEC oad is imited per interna breaker factor of safety Basic & 50 20 20 60A 3 Phase with 6 each 2 poe breakers Input Power: (60A) (208V) (1.73) (80%) = 17.3kW 60A breaker at pane unit de-rated to 48A per UL / NEC oad is imited per UL / NEC 20 20 20 20 20 2 poe breaker imits oad Load shoud be de-rated to 16A Lyz - 20A 2 poe breaker imits oad Load shoud be de-rated to 16A Lzx - 20A 2 poe breaker imits oad Load shoud be de-rated to 16A Output Power: 3 circuits, 20A/circuit Output Power: (3) (20A) (208V) (80%) = 10kW Lxy - 17.3A Lyz - 17.3A Lxz - 17.3A Lxy - 17.3A Represents mutipe receptaces per circuit 20 20 20 20 Lxy=11.5A Lyz=11.5A Lxy=11.5A Lyz=11.5A Lxy=11.5A Lyz=11.5A Lxy=11.5A Lyz=11.5A Output Power: 12 circuits, 20/1.73 circuit Output Power: (12) (11.5A) (208V) (80%) = 23kW Input Power: (60A) (208V) (1.73) (80%) = 17.3kW 60 60A 3 Phase with 3 each 3 poe breakers 60A breaker at pane unit de-rated to 48A per UL / NEC oad is imited per UL / NEC 20 20 Lxy=11.5A Lyz=11.5A Lxy=11.5A Lyz=11.5A Lzx=11.5A Lzx=11.5A Lzx=11.5A Lzx=11.5A Lzx=11.5A Lzx=11.5A Switched Sateite Environmenta Software Accessories Brackets Educationa Resources 20 20 Lyz - 17.3A Lxz - 17.3A Output Power: 6 circuits, 17.3A/circuit Output Power: (6) (17.3A) (208V) (80%) = 17.3kW 20 Lxy=11.5A Lyz=11.5A Output Power: 12 circuits, 20/1.73=11.5A/circuit Output Power: (9) (11.5A) (208V) (80%) = 17.3kW Lzx=11.5A 800-432-3219 181

Educationa FAQ - Geist Specific Basic & Sateite Switched Software Environmenta How can Geist turn customized products in 1 week, when others take months? Geist has the argest in-house engineering department in the industry. Geist s in-house engineering department incudes mechanica, eectrica, conformance, board ayout and software speciaists. The testing ab at Geist is authorized to conduct UL testing on Geist products to 60950 IT Equipment standards as part of the UL Data Acceptance Program. Our software speciaists can create software for new or custom products and depoy directy to production to reduce ead times. Geist aso has an in-house team responsibe for Embedded Circuit design, which aows for faster turnaround on custom appications requiring circuit boards. Geist s engineering team is dedicated to providing the highest quaity products and service avaiabe in the industry. Resources Educationa Brackets Accessories Geist invests in continuous improvement. The Geist Metaworks division aows us to punch, bend and paint our own meta products. This aows Geist to reduce aready short ead times by eiminating scheduing conficts with suppiers. The Geist Metaworks team aso heps reduce the ead time on custom units, making products avaiabe to the customer faster than ever before. 182

Educationa FAQ - Geist Specific Can Geist provide a basic Current Meter that does not scro through the additiona power information incuding Votage, Watts and Power Factor? Geist singe phase PDU s containing the Power Meter have the option of being purchased with a rea-time meter that dispays ony the Amp reading for the unit. Pease contact your Customer Service Representative at 800-432-3219 for a part number modification with this optiona factory configuration. Seection must be made at the time of purchase. How do I connect mutipe units from 1 IP address? Use a router or a switch with routing capabiities. The router connects to your network using one IP address and routes traffic to and from the connected devices in their own separate address space. For exampe, if you had 3 devices you coud assign IP addresses 10.0.5.2, 10.0.5.3 and 10.0.5.4 to those devices, and 10.0.5.1 to the device side of the router (this is caed the gateway, and typicay is assigned the first IP address in a given range). The network side of the router woud then be assigned a network address on your existing network. See page 73 for an iustration of this concept. Geist Has Gone Goba Geist now offers an extensive ine of power distribution units (PDUs), in-ine meters and environmenta monitoring products that can be used around the word. Geist s goba products compy with the harmonized IEC 60950 standard for Information Technoogy Equipment. In addition, Geist s goba products... - carry the CE mark for European Union safety and emissions conformance. - are tested by UL, and are backed by Underwriters Laboratory Certification Body (CB) report. - are RoHS compiant. - are C-Tick compiant to meet eectromagnetic compatibiity requirements for Austraia and New Zeaand. Geist s goba PDUs are avaiabe in a variety of configurations to meet your needs: - Remote modes (monitored or switched), as we as oca modes (basic or metered) - 16A, 32A or 48A - singe phase or 3 phase - 50Hz and 60Hz compatibiity - Avaiabe with either IEC 60309 pin & seeve (Commando) pugs or IEC 60320 C-20 input feeds - Gobay accepted IEC 60320 and/or C-19 outet receptaces Like our PDUs, Geist s in-ine meters come in many configurations, which is enough to serve any monitoring requirement. Geist s fu range of environmenta monitors are aso gobay compatibe. When ordering, just specify where the unit wi be used and Geist wi ship it with the appropriate power suppy for that region. Basic & Switched Sateite Environmenta Software Accessories Brackets Educationa Resources With Geist s extensive goba offerings, specifying a singe configuration wordwide is easy. Visit www.geistint.com 800-432-3219 183

Educationa FAQ - Power Specific Basic & Sateite Switched Software Environmenta Accessories Brackets Resources Educationa What rating shoud I use to correcty seect a PDU for my instaation? There are severa factors to consider when seecting a Geist PDU to ensure that the PDU has sufficient capacity for the intended appication. The three main factors to consider are (1) namepate rating, (2) receptace ratings, and (3) interna breaker configuration. NAMEPLATE: The namepate rating marked on a Geist PDU is the intended operating votage range and imum operating input current. Namepate ratings are based on both reguatory requirements and design factors and represent the continuous tota current that the PDU wi be abe to deiver to a oad. The PDU shoud not be instaed in an appication where the namepate ratings are exceeded. RECEPTACLE: The PDU s output power is connected to information technoogy equipment through either NEMA or IEC receptaces. The PDU shoud not be instaed in a manner that wi exceed the imum current rating of any individua receptace. For exampe, a NEMA 5-15R receptace shoud not be oaded to over 15A regardess of the namepate rating of the PDU it is instaed in. INTERNAL BREAKERS: Geist Manufacturing s PDUs can be equipped with interna circuit breakers that are used to protect the circuit in case of overoad or earth faut conditions. For PDUs rated 12A or 16A, the circuit breakers are optiona components that act as suppementary protectors. For PDUs rated higher than 16A, the circuit breakers are required components that provide primary overcurrent and earth faut protection for the PDU s interna circuits. The PDU shoud not be connected to a oad that wi exceed the current rating of an interna breaker. For imum protection against nuisance tripping, it is recommended that interna breakers are ony oaded to 80% of the breaker current rating. Can I purchase a PDU without a circuit breaker? Yes, some configurations can be purchased without an interna circuit breaker. A Geist Manufacturing s PDUs require an appropriatey sized branch circuit breaker in the buiding instaation. Branch circuit breakers shoud be sized according to the PDUs nampate rating, and eectrica code requirements. To compy with the NEC the circuit breaker in the buiding instaation shoud have a trip current rating that is 25% higher than the PDU s namepate. For exampe, a 16A rated PDU requires a 20A circuit breaker. How do I determine how much power is needed in a cabinet? Perform the foowing for a quick estimate of the power needed in a cabinet: Add the power ratings in Watts (W) from the namepate abes of the equipment you want to put in the cabinet. {Sometimes, the abes indicate Amps (A) instead of Watts (W). In this case, mutipy Votage (V) and Current (A) vaues to get an approximate vaue for power.} Exampe: 30 servers each using 300 Watts = 30 x 300 = 9,000 Watts, or 9kW. The chart on page 180 shows the reationship between singe and three phase power feeds and the associated kw oad that they wi support when de-rated by 80% per UL/ NEC requirements. Additiona information about heat oad, air conditioning requirements and air voume requirements is aso incuded for reference. Why are Geist cord-connected units isted with a de-rated Amperage? Geist s cord-connected PDUs carry a namepate current rating that is 80% of the branch circuit rating isted in the cataog specification. The namepate current rating has been owered in order to compy with UL /NEC requirements. Geist PDUs are UL Listed as Information Technoogy Equipment to the UL 60950 Standard. UL 60950 requires that the attachment pug of Listed Information Technoogy Equipment sha be rated not ess than 125% of the Rated Current of the equipment at the nomina system votage range as defined by the configuration of the pug. This cause in UL 60950-1 is based on the requirements of the Nationa Eectrica Code (NFPA 70) which state that branch circuit conductors and overcurrent protection devices sha be sized to carry 125% of the continuous oad and 100% of the non-continuous oad on the circuit breaker. Due to this UL /NEC requirement, the namepate current rating of a Geist PDU is 80% of the imum current rating of the branch circuit used to power the PDU. Most of Geist s customers base their PDU input current specifications on the branch circuit ratings; consequenty, the cataog ists the ratings of the branch circuit that the PDU is intended to be connected to. In addition to the branch circuit rating, it is important to consider the nampeate PDU rating which incudes the 80% de-rating factor required by UL /NEC when cacuating PDU requirements. 184

Educationa FAQ - Power Specific Why shoud I consider designing my data center with 208V instead of 120V? The eectrica power consumption of eectrica appiances is measured in Watts (W). Wattage (Watts vaue) is a product of the rated Votage (V) and Current (I). W = V x I. The higher the Votage the ower the current required to suppy the same Watts. The same size wire can carry neary 2x as much power (Watts) @ 208V versus 120V. A Votage of 208V instead of 120V, yieds 1.73 times more power. What are the benefits of utiizing two 20A breakers versus two 15A breakers on a 30A PDU? 20A breakers in a 30A unit aow imum fexibiity of oad connection without nuisance tripping. The receptaces in a 30A PDU are divided into two independent groups. A 30A PDU distributing to 15A or 20A receptaces must be broken down into either 15A or 20A circuits internay. By opting for 20A interna circuits, PDU circuit baance is ess critica. One circuit may be oaded to >15A. This woud not be possibe if each breaker were rated at 15A. Can you distribute both 120V and 208V from a PDU with a singe input cord? PDUs with 3 Phase WYE input aow for the option of distributing 120V and 208V in a singe power strip. 3 phase WYE consists of 3 Phases, 1 Neutra and 1 Ground conductor. 208V output is achieved across two phase conductors and 120V output is achieved across one phase conductor and the neutra conductor. See diagram on page 177. How does Wattage reate to heat in a cabinet? Heat is measured in Watts. Power is measured in Watts. Amost a eectrica energy used in computing is converted to heat. A computer power suppy can be as ow as 80% efficient. This means that for every 100 Watts it draws, 20 Watts may be converted directy into heat without ever being used by the computer. As the computer processes information, the rest of the power is dissipated throughout the system as heat. Since a power can be counted as heat, adding the Watt ratings of a equipment in a cabinet wi give a reativey 1:1 reationship to heat generated. Exampe: 40 servers x 300 Watts each = 12,000 Watts (12kW) heat. Why can t I output 120V from a 208V singe phase input? Geist Manufacturing Power Distribution Units (PDUs) are high quaity power strips intended to be used to distribute power to information technoogy equipment within a datacenter. These PDUs, which are avaiabe in singe or three phase configurations, are not designed to increase or reduce the input circuit s votage eve. Singe Phase 120V rated power distribution units instaed in North America wi typicay be powered by a 120V ineto-neutra circuit. The outets on these PDUs wi a be wired ine-to-neutra and wi output 120V. Singe Phase 208V rated power distribution units instaed in North America wi typicay be powered by a 208V ine-to-ine circuit. The Neutra conductor is not connected to a standard 208V singe phase PDU; consequenty, a outets wi be wired ine-to-ine and wi output 208V. What are the advantages of bringing 3 Phase power to my cabinet? 1) Less wire under the foor improves airfow and reduces wiring confusion. A 20A 3 Phase instaation contains 5 wires where the equivaent singe phase system woud require 9 wires (3x3). 2) Fewer whips to pu saves you time and money. A 3 Phase system has one whip for the eectrician to bring to the cabinet where the equivaent singe phase system woud have 3 whips. This saves both materia and abor cost. 3) Simpified oad baancing reduces technician instaation and troubeshooting time. With a 3 Phases avaiabe in a singe cabinet, oad baancing can be achieved at the cabinet eve where simiar type equipment is often found. In a singe phase system, a minimum of 3 cabinets may need to be ooked at to baance the same oad. Basic & Switched Sateite Environmenta Software Accessories Brackets Educationa Resources 800-432-3219 185

Educationa FAQ - Industry Topics Basic & Sateite Switched Software Environmenta What is the difference between a circuit breaker or surge suppressor? CIRCUIT BREAKER A circuit breaker is a device that opens and coses an eectrica circuit. It senses the current fow and operates automaticay when the current exceeds the breaker s trip threshod. Human intervention is required to switch the circuit back on. A circuit breaker is current imiting and is used to protect the wire within an instaation. Magnetic Breaker / Switch Push to reset Can Geist provide a unit with a Penum Rated power cabe? Geist is peased to offer UL Listed DP-1 Rated cabe, with an FT-4 fame rating, as an option avaiabe on most Geist PDUs. Pease contact us at 800-432-3219 for assistance with your specific appication or additiona information. Are VISIO stencis avaiabe for Geist products? Geist Manufacturing has partnered with Atima Technoogies to create visio shapes from standard Geist products. Shapes can be downoaded using Atima s NetZoom software which is avaiabe at www.atimatech.com. You can aso contact your Geist CSR to request Visio shapes. Accessories Brackets Resources Educationa Therma Circuit Breaker SURGE SUPPRESSOR A surge protector imits the magnitude of the votage in an eectrica circuit without interrupting the current fow. It is used to prevent votage spikes from damaging eectrica equipment. Surge Suppressor How does RoHS compiance affect me? RoHS is an acronym for Restriction on the use of Certain Hazardous Substances. The term RoHS is most commony used to refer to the European Union s (EU) RoHS Directive. The objective of the EU RoHS directive is to restrict the use of hazardous substances in eectrica and eectronic equipment. This reduction is intended to both reduce the amount of hazardous substances in andfis resuting from the disposa of eectrica and eectronic equipment and to minimize the heath and environmenta impact of recycing eectrica and eectronic equipment. RoHS Compiance is mandatory for PDU products sod in Europe, and is becoming increasingy more important for PDU products sod in the United States. For exampe, Caifornia has aready passed Proposition 65, a RoHS-ike aw requiring certain eectrica and eectronic equipment to compy with the requirements estabished by the EU RoHS Directive. 186

Educationa FAQ - Industry Trends & Best Practices What gets measured, gets improved. How do you measure Green? Geist Manufacturing can hep you capture return on green initiatives by providing the metrics you need, heping you decrease your carbon footprint. Whether it s monitoring power consumption per server via outet eve monitoring or ooking at environmenta conditions within your data center, Geist has a soution for your monitoring needs. IP accessibe units provide rea-time feedback of actua data center conditions. MOTORS Fans Chiers VA (bied $) WATTS (used) WATTS - - - - - - - - - - - - - - - - - - - - - - - - - - better - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - better IT LOAD Switch Mode P.S VA (bied $) INDUCTIVE VAR VAR (wasted $) Lagging PF CAPACATIVE VAR VAR (wasted $) Leading PF Power Triange The Power Triange iustrates the inefficiency of typica equipment connected to AC power. Losses in an AC power oad are primariy inductive or capacitive, expressed as reactance. Inductive osses are the resut of magnetic opposition to current fow (motors, cois and transformers). Capacitive osses often arise from modern switching power suppies found in most IT equipment. Both types of osses resut in wasted energy, as the energy deivered from the utiity (VA) is greater than the work performed by that energy (W). The difference (VAR) represents wasted energy doars. A perfecty baanced AC oad, where the inductive reactance equas the capacitive reactance, woud resut in a perfect use of deivered energy. In this case VA equas W, VAR is equa to zero, the Power Triange becomes a straight ine, and a energy deivered is used to perform work. This is aso caed unity Power Factor (PF = W/VA). A PF ess than one indicates inefficiency and wasted energy. What are the best products and practices for true redundancy? Mission Critica data centers design redundancy into their power systems, often taking dua feeds of power from the buiding entrance a the way to the cabinet. The basic tenant of redundancy is to reduce or eiminate singe points of faiure. For this reason, it is generay accepted practice to use two separate PDUs within each cabinet rather than one, dua-corded PDU. This practice maintains redundancy and eiminates the potentia of a singe point of faiure in the power system. There is, however, some critica thinking that goes aong with cabinet eve PDU oading. Since each server is ikey to be running on two separate power suppies, each power suppy shoud ony be handing ½ of the tota server oad. By extending this thinking to the entire cabinet eve PDU, each of a redundant set of PDUs shoud ony be oaded to ½ of the PDU s rated oad. To oad the cabinet eve PDU to greater than ½ of its rated oad coud ead to a cascade faiure if one power feed is interrupted. The shift of the entire server oad onto the remaining PDU woud overoad the circuit protection and utimatey trip breakers, eaving the cabinet poweress. One of the simpest ways to track cabinet eve PDU oading is to invest in, at a minimum, ocay monitored PDUs. Technicians can observe the curent oad as cabinets are popuated, ensuring that each PDU is oaded to no greater than ½ of the rated output current. Once the oad has been achieved the remaining unused outets shoud be bocked. Refer to Pug Outs and Pug Shieds on page 170. Why is density such a hot topic in data centers recenty? Cassic physics defines density as mass/unit voume. In the data center, density is used in a different context. Density is referred to when cabinets are fied with power consuming equipment, eading to high power density and heat density. In past years, data center designers designed to accommodate certain power eves per square foot of raised foor space. Now, the trend is to consider power eve per cabinet. For instance, 5-10 years ago, the norm was to oad cabinets to 3-4 kw. Current servers use faster, more power hungry processors, eading to more power consumption. Cabinets fied with 1U servers, or bade servers, can draw upwards of 20kW. This high power consumption in a reativey sma amount of space is referred to as high power density, or simpy high density computing. Geist offers severa PDUs idea for high density computing, with PDUs ranging up to 34kW. Basic & Switched Sateite Environmenta Software Accessories Brackets Educationa Resources 800-432-3219 187

Educationa FAQ - Best Practices Basic & Why monitor current draw at the outet eve? Monitoring current at the outet eve aows you to pinpoint potentia system-critica faiures and take preventative measures. A gradua rise in system current draw might indicate a power suppy or cooing faiure. A sharp spike might indicate a short circuit. Outet eve monitoring can aso hep track where power is being used. Outet monitoring is aso an easy way to accomodate departmentaized power biing within arge companies whose data centers serve severa departments. The screen shots beow are from the XPWM249-103M46TL21-OM found on page 84. Contact your Customer Service Representative to review your specific needs. Resources Educationa Brackets Accessories Software Environmenta Sateite Switched 188

Educationa FAQ - Best Practices What is the importance of branch circuit monitoring at the PDU eve? Branch Circuit Monitoring is often promoted by Remote Power Pane (RPP) manufacturers as the best way to coect IT oad data and prevent downtime due to circuit overoading. In most of today s data centers, that is not true. Most branch circuit depoyments in modern data centers are above 30 Amps, which means the power strips depoyed in the cabinets must be broken down into sub-circuits sized for the receptaces within the strips. A 30 Amp strip, for instance, wi contain at east two branch circuits internay to satisfy the requirements of the NEC and sti aow the user access to a of the avaiabe power. Higher power units, such as 60 Amp x 3 Phase units can contain up to 6 interna circuits to satisfy the NEC and sti aow access to a avaiabe power. Monitoring at the strip eve in these instances aows more granuar power readings. In a 30 Amp singe phase power strip, for exampe, it woud be best to monitor the incoming current and both interna branch circuits. Monitoring the input phase currents can give warnings to the end user if the overa current is about to breach the threshod of the remote power pane mounted branch circuit protector. Monitoring of each individua circuit within the strip is sti necessary. This sub-circuit monitoring can not ony ensure that the interna branch circuits are not overoaded, but can aso hep in propery baancing the oad between the interna circuits. Interna oad baancing within the power strips becomes more critica in 3 Phase oads, where there can be more interna circuits to baance. 30 Amp x 3 Phase power strips contain three interna circuits. If 208V depoyment is used, the breakers each draw current off of two different phases, further compicating the monitoring. In this instance, it woud be idea to monitor the three input phases (X, Y, Z) as we as the interna sub circuits which each draw power off of two different phases (XY, YZ, ZX). Monitoring the sub circuits aows the oads to be eveny baanced over the 3 Phases and prevents overoading of any of the interna sub circuits. Monitoring the phase currents aows visibiity of the oad paced on the RPP mounted branch circuit. Monitoring at the power strip eve gives the cearest reading of the actua IT oad within the data center. When cacuating PUE or DCiE, or any other metric that uses the IT oad, the IT oad shoud be continuay monitored as cose to the actua IT oad as possibe. By monitoring in the power strip, the oad is not affected by energy osses inherent within the power chain. The prominent osses associated with UPS and transformers, as we as osses in switchgear and due to wire run ength, are discarded by monitoring at the strip eve. This gives the cearest and most accurate view of the IT equipment oad. Monitoring continuousy gives the best visibiity of the oads. This aows the user to see a data and trend it over time, as opposed to momentary monitoring (houry, daiy, weeky) which can miss peak usage times. Why shoud I consider designing my data center with 230/400V 3 Phase? The standard power distribution system for arge data centers in North America is a 277/480V three-phase power system. A typica data center uses distributed transformers to convert the votage to 120V and 208V singe-phase branch circuits for powering the IT equipment. Most of the rest of the word uses 230/400V power, which is simper and more efficient to use. Converting from 277/480V to 230/400V can be accompished using an autotransformer, which is cheaper, ighter, smaer and wastes ess power than a conventiona transformer. This aso means ower cooing costs, as the autotransformer can be ocated outside the data center. Modern IT equipment can use an input votage anywhere from 100V to 240V, so a 230V branch circuit can power amost anything found in a modern data center. Since the power used by a given oad is the product of Votage times Current (see page 176), more power can be deivered to a rack using the same wiring. Power density can be increased without using additiona breakers. Conversey, smaer gauge wire can be used to suppy the same power to a given oad. Either way, there is a cost savings in equipment required to deiver power to the oad. Use of the internationa 230/400V distribution system instead of the standard 120/208V system can save up to 56% in the ifetime cost of the distribution system. 230/400V PDUs can be found in the foowing sections: Basic & 20A - Page 44 20A - Page 80 30A - Page 64 30A - Page 85 Switched Sateite 20A - Page 108, 116 20A - Page 125 30A - Page 110, 118 30A - Page 130 What types of pugs does Geist offer on 230/400V 3 Phase PDUs? Geist offers 230/400 V, 3 Phase PDUs in two different pug configurations. These units are avaiabe with either a Pinand-Seeve stye pug or a NEMA pug. The NEMA pugs used on these units wi either be a L22-20P or an L22-30P depending on the unit s namepate current rating. It is important to note that athough the L22-20P and L22-30P pugs carry a votage rating of 277/480 V, the PDU is sti ony intended to be powered by a 230/400 V, 3 phase source. Units that use the NEMA pugs wi have an additiona tag on the power cord to remind the user to ony connect the PDU to a 230/400 V, 3 phase power suppy. L22-20P L22-30P Basic & Switched Sateite Environmenta Software Accessories Brackets Educationa Resources 800-432-3219 189

Appication Drawing Cabinet View RT (remote temperature sensor) Page: 164 Basic & RTHD (remote temperature & humidity sensor) Page: 164 RDPS (remote door position sensor) Page: 165 RTAFH (remote temperature, air f ow & humidity sensor) Page: 164 RTAF (remote temperature & air f ow sensor) Page: 164 Power Monitoring Pus Unit Pages: 98-102 Sateite Power Monitoring Pus Unit Pages: 136-141 Brackets Accessories Sateite Switched Software Environmenta Resources Educationa RWS (remote water sensor - singe point sensing) Page: 165 WSCK (water sensing cabe kit - perimeter sensing) Page: 166 190

Appication Drawing Cabinet View Geist offers a myriad of soutions that aow for remote monitoring of power consumption, environmenta conditions, or both within the same units. By incorporating environmenta monitoring together with power monitoring, a singe Ethernet connection can be used to monitor both the power consumption and the other conditions that can affect the operation of sensitive IT equipment. Prompt notification upon breach of power, temperature, or humidity threshods can iteray save the ife of the equipment and hep prevent downtime within the IT system. Basic & POWER MITORING PLUS UNIT These master units aow combined cabinet eve power and environmenta monitoring in a singe unit with a singe Ethernet connection. Onboard sensors show power measurements such as current and votage, as we as environmenta conditions such as temperature, humidity, ight eve, sound eve, and airfow. Pages: 98-102 SATELLITE POWER MITORING PLUS UNIT Aow monitoring of additiona power strips (in the case of A and B feeds) via the Power Monitoring Pus Unit. This aows for expanded power monitoring within a cabinet with a singe Ethernet connection. Pages: 136-141 RWS / WSCK Point or perimeter water sensing can be fed back to Power Monitoring Pus units by using either a Water Sensing Cabe Kit or a Remote Water Sensor. Perimeter sensing is convenient in determining if moisture is present over arge under foor areas. Point moisture sensing may be used in evaporator trays in or around HVAC systems. Pages: 165-166 RT Various combinations of temperature sensing combined with other psychometric data are avaiabe in Geist s sensor ine, incuding temperature sensors that add parameters such as humidity, dew point, and/or airfow measurements. Temperature measurements are critica in eary notification of potentia probems that can ead to server faiure. Page: 164 RTAFH Humidity can be important in determining if dry conditions can ead to static discharge, which can ead to eary faiure of sensitive eectronic equipment. Page: 164 RTHD Dew Point measurements can aert to the potentia of condensation probems. This can be especiay important in sma, distributed cabinets such as those often found in arge, industria appications. Page: 164 RTAF Air Fow measurements can provide critica data about fan functionaity, potentiay aerting personne of fan faiure before temperatures rise to critica eves. Page: 164 Switched Sateite Environmenta Software Accessories Brackets Educationa Resources RDPS Door position sensors can provide remote aerts to cabinet or room intrusion, and be used as part of security audits in co-ocation faciities. Page: 165 800-432-3219 191

Appication Drawing Data Center Room View Bade Server Cabinet Co-Location Cabinet Computer Room Air Conditioner / Computer Room Air Hander Switch Cabinet 1 U Server Cabinet Resources Educationa Brackets Accessories Basic & Sateite Switched Software Environmenta 192

Appication Drawing Data Center Room View Geist Manufacturing offers power distribution and monitoring soutions for a variety of data center environments. Athough this graphic shows an unikey pairing of cabinets, the variety of soutions suggested in the foowing paragraphs demonstrate some possibe soutions avaiabe from Geist. COMPUTER ROOM AIR CDITIERS / COMPUTER ROOM AIR HANDLERS (CRACs / CRAHs) - An idea pace for Geist Environmenta units, which aow for remote monitoring of incoming and outgoing air temperatures, humidity measurements, and other critica environmenta conditions. Additiona remote sensors, such as water sensors, can be added to monitor moisture in CRAC drain pans. Pages: 146-159, 164-167 SWITCH CABINETS - Typicay defined by ow power consumption and heat oad, Geist s Current Monitoring or Sateite Current Monitoring 20 Amp (VHV) and 30 Amp (XP) series power distribution are economica and ogica approaches for switch cabinets. Pages: 78-84, 123-129 1U SERVER CABINETS - 1U server cabinets present the greatest chance for ocked equipment. Geist s Switched, Switched Utra and Sateite Switched units aow for remote rebooting of ocked servers, as we as aowing for remote monitoring of cabinet environmenta conditions with the addition of remote environmenta sensors. Pages: 104-110, 112-118, 142-144 BLADE CABINETS - Geist ZP series PDUs outfitted with Current Monitoring or Sateite Current Monitoring simpify management of high power appications such as bade server cabinets. ZP series PDUs sove power distribution probems of up to 34 kw with singe power feeds. Geist environmenta monitoring units can add critica temperature monitoring to heat generating bade cabinets. Pages: 86-89, 131-134 CO-LO CABINETS - Co-Location Cabinets are an idea pace for Power Monitoring Pus units, aowing remote, secure monitoring for environmenta, power, and security status. Mutipe security eves aow end users visibiity of cabinet conditions and provide for a secure audit trai. Pages: 98-102 Basic & Switched Sateite Environmenta Software Accessories Brackets Educationa Resources 800-432-3219 193

Appication Drawing Campus View Basic & Sateite Switched Software Environmenta Accessories Brackets Resources Educationa (1) REMOTE TOWERS / OUTSIDE PLANT STATIS Proximity and ease of access for remote/off-site IT ocations can present distinct chaenges for minimizing down-time. It is imperative for today s IT manager to have remote access to reboot ocked equipment in addition to monitoring site environmenta conditions. Geist Soutions Switched Pages: 104-110 Switched Utra Pages: 112-118 Sateite Switched Pages: 142-144 Remote Sensors Pages: 164-167 (2) WIRING CLOSETS These dedicated spaces, ocated across your campus, house network and teecommunications equipment critica to providing reiabe and secure communications. Wiring cosets are exposed to a variety of environmenta and power conditions, uniquey different from your data center, and are often overooked in up-time panning unti a probem arises. Geist Soutions Environmenta Products Pages: 146-159 Power Monitoring Pus Pages: 98-102 1 2 3 194

Appication Drawing Campus View Basic & 2 2 2 4 1 2 1 (3) DATA CENTER Power distribution varies greaty from one data center to the next. However, the need for power and environmenta monitoring remains constant for a instaations. From ow power consumption in the 2-5 kw range up to bade server appications utiizing 8-34 kw per cabinet, instaers and technicians benefit from immediate power consumption feedback with oca monitoring. Geist Soutions Pages: 6-70 Current Monitoring Pages: 72-89 Power Monitoring Pages: 90-96 (4) NETWORK OPERATIS CENTER (NOC) The Center of your Instaation with utimate responsibiity for monitoring a conditions impacting the networks performance requires precise, timey and reative data via standard communication protocos such as SNMP, HTML, XML, BACNET, Modbus, and L. Geist Soutions Consoe Management Software Pages: 160-161 Environet Pages: 162-163 Switched Sateite Environmenta Software Accessories Brackets Educationa Resources 800-432-3219 195