S & C E L E C T R I C C O M P A N Y

Transcription

1 Descriptive Bulletin September 11, 2006 Supersees Descriptive Bulletin ate

2 Here Are Five Reasons Why Loabuster Is the Better Way: 1 Range S&C s Loabuster unlike loabreak cutouts or hookstick-operate interrupter switches brings loa switching capability through 34.5 kv an 600 amperes nominal, 900 amperes maximum to your overhea istribution system. You can even switch ungroune transformers at 27 kv or 38 kv. No longer must you labor uner the assumption of a limite voltage or current spectrum for loa-switching evices on your istribution system. An with Loabuster, the ollar savings are big Greater Flexibility... at Lower Cost Having an arc-interrupting means built into every isconnect, cutout, power fuse, fuse limiter, an ropout recloser on your overhea istribution system is a prohibitive luxury it simply costs too much. S&C s Loabuster gives you the operating flexibility of a system with multipoint interrupter switches but without the cost. How? Loabuster S&C s portable loabreak tool brings the interrupter to the isconnect, cutout, power fuse, fuse limiter, or ropout recloser whenever loabreak switch capability is neee... instantly. But only when neee. The rest of the time, these S&C Loabusteroperable evices remain matche to the economics of the system. Loabuster is S&C s unique metho of proviing low-cost, positive, an convenient loa-switching capability for evices esigne for Loabuster operation. The concept is simple. The avantages are many. The beauty of it all is that Loabuster can be instantly reset for repeate use... so you limit your investment to only one Loabuster Tool for each line truck, you sprea an acceptable minimal cost across your system, an you can move quickly to restore service to power consumers. There are two ways to perform single-phase live switching on a istribution system... interrupter-equippe cutouts an isconnects. Or the better way: S&C s portable loabreak tool: Loabuster. Power Consumers Benefit with Loabuster No one likes to be without electric power. An most power consumers cannot tolerate prolonge outages... not even short breaks in service. Loabuster switching helps keep service interruptions to a minimum. There s no nee for complex switching proceures involving opening an reclosing of line an feeer breakers to permit ea switching. There s no nee for one or more line crews to travel an retravel miles of system. Loabuster makes every isconnect, cutout, power fuse, fuse limiter, an ropout recloser a sectionalizing point. Live switching can be one at the point that minimizes the length of planne outages an/or the point where the fewest power consumers will be affecte. Operating Personnel Like Loabuster Loabuster is easy to operate. Loabuster s anchor is simply hung on the attachment hook of the isconnect, cutout, power fuse, fuse limiter, or ropout recloser. Then the pull-ring is engage with Loabuster s pull-ring hook, hel fast by the pull-ring latch (see page 6). A firm, steay ownwar pull opens the evice an trips Loabuster, breaking the circuit. There s no external arc, no contact burning. Loabuster-operable evices have no ubious arc chutes, auxiliary blaes, or mechanisms to concern operating personnel. An, being portable, Loabuster is always available for easy inspection. A minimum of attention assures operating personnel that it s in top-notch conition. 2

3 5 Universality Loabuster Does More Than Switch Loa In combination with portability, another concept, universality, has been emboie in Loabuster. Not only can Loabuster switch loa currents up through 600 amperes nominal, 900 amperes maximum at istribution system voltages up through 34.5 kv... it can break the associate transformer-magnetizing currents, line-charging currents, an cable-charging currents. An it can switch single capacitor banks typically foun on istribution systems within its voltage rating, as spelle out in the table on page 4. Certain restrictions apply... see the limitations on page 5. Loabuster brings switching capability to suitably hook-equippe isconnects, cutouts, power fuses, fuse limiters, an ropout reclosers. It thus eliminates the nee for loabreak cutouts or hookstick-operate interrupter switches... even group-operate isconnects or interrupter switches where group operation is unnecessary. Loabuster Catalog Number 5300R3 Rate: 14.4/25 kv Nominal 27 kv Maximum Loabuster Catalog Number 5400R3 Rate: 25/34.5 kv Nominal 38 kv Maximum Optional Carrying Case Double-wall, high-ensity polyethylene construction provies extraorinary protection for Loabuster. 3

4 Loabuster Switches a Wie Range of Devices Consiering its universality an switching capabilities, Loabuster s easy-to-operate esign is all the more remarkable. Loabuster can be use with all hookequippe istribution evices incluing isconnects an cutouts not manufacture by S&C when they qualify for switching with Loabuster. See the quantitative requirements outline on page 8. Switching a Disconnect Loabuster Catalog Number 5400R3 use with a 34.5-kV Crossarm Inverte Style Loabuster Disconnect Switching a Cutout Loabuster Catalog Number 5300R3 an 25-kV Ultra-Heavy-Duty Overhea Pole-Top Style S&C Type XS Cutout are a perfect match for protection an switching Switching a Power Fuse Loabuster Catalog Number 5400R3 brings switching capability to a 25-kV Overhea Pole-Top Style S&C Type SMD-20 Power Fuse Switching an S&C Fault Tamer Fuse Limiter Loabuster Catalog Number 5300R3 is shown here switching a 15-kV S&C Fault Tamer Fuse Limiter Switching an S&C TripSaver Dropout Recloser Loabuster Catalog Number 5300R3 applie with 15-kV Branch-Feeer Style TripSaver Dropout Recloser Switching Ratings Loabuster is available in two easy-to-use moels: Catalog Number 5300R3, rate 14.4/25 kv nominal, 27 kv maximum; an Catalog Number 5400R3, rate 25/34.5 kv nominal, 38 kv maximum. Both have a 50/60-hertz interrupting rating of 600 amperes nominal, 900 amperes maximum. When use with suitably hook-equippe isconnects, cutouts, power fuses, fuse limiters, an ropout reclosers, Loabuster is suitable for these live-switching uties on singlephase or three-phase circuits of overhea istribution systems through 34.5 kv: Transformer switching Loabuster can switch transformer loa currents up through 600 amperes nominal, 900 amperes maximum, as well as transformermagnetizing currents associate with the applicable loas. Line switching Loabuster may be use for loa splitting (parallel or loop switching) an loa ropping of currents up through 600 amperes nominal, 900 amperes maximum. It is also capable of line ropping (charging currents typical for istribution systems of these voltage ratings). Cable switching Loabuster is suitable for loa splitting (parallel or loop switching) an loa ropping of currents up through 600 amperes nominal, 900 amperes maximum. It may also be use for cable ropping (charging currents typical for istribution systems of these voltage ratings). Capacitor bank switching Loabuster can switch single capacitor banks to the extent reflecte in the table below. Capacitor-Bank Switching Capability Loabuster Catalog Number 5300R3 5400R3 Nominal System Voltage, kv, Three-Phase an an Maximum Capacitor Bank Rating, kvac, Three-Phase Solily or Effectively Groune System Single1 Banks, Groune- Wye Connecte Single1 Banks, Ungroune- Wye Connecte Ungroune System Single1 Banks, Groune- or Ungroune- Wye Connecte Loabusters must not be use for switching parallel ( back-toback ) capacitor banks. Loabusters must not be use for switching ungroune-wye connecte banks or groune-wye connecte banks on ungroune systems where maximum system operating voltage excees 18 kv for Loabuster Catalog Number 5300R3, or 29 kv for Loabuster Catalog Number 5400R3. 4

5 A Note on Single-Pole Switching In single-pole switching of ungroune-primary three-phase transformers or banks (or single-phase transformers connecte line-to-line), circuit connections or parameters may, in some cases, prouce excessive overvoltages. In particular, for the following applications above 22 kv, single-pole switching by any means incluing Loabuster shoul be performe only uner the conitions state in italics: h For unloae or lightly loae elta-connecte or ungroune-primary wye-wye connecte three-phase transformers or banks (or line-to-line connecte singlephase transformers), rate 150 kva or less three-phase, or 50 kva or less single-phase or of any kva rating when combine with unloae cables or lines where maximum system operating voltage excees 22 kv. Single-pole switching shoul be performe only if each phase is carrying 5% loa or more, or if the transformer or bank is temporarily groune at the primary neutral uring switching. h For loae or unloae ungroune-primary wye-elta connecte three-phase transformers or banks alone or combine with unloae cables or lines where maximum system operating voltage excees 22 kv. Single-pole switching shoul be performe only if each phase is carrying 5% loa or more an if the lightingloa phase is always switche open first (or switche close last); or if the transformer or bank is temporarily groune at the primary neutral uring switching. Operating Life Loabuster is a stury an reliable tool that will provie years of excellent service. Only a minimum of attention is require to keep it in top-notch operating conition. Inspection intervals are ictate by the number of operations as inicate on the operation counter an the severity of switching uties. Asie from the counter reaing, there are no auible or visible signals to inicate the nee for attention. From 1,500 to 2,000 Loabuster operations may normally be expecte between require inspections, base on typical usage involving a mixture of varie switching uties. Inclue in these uties are switching of line-charging currents, transformer-magnetizing currents, pole-top capacitor-bank currents, an moerate parallel or loop loa currents, with only occasional switching of heavier loa currents. Only if Loabuster is use primarily for switching of loa currents approaching the rating of the tool will more frequent inspections be require. Benchmarks inicating the nee for replacement of Loabuster parts inclue the egree of erosion of the trailer portion of the moving contact assembly an the conition of its flexible cable. The simplicity of Loabuster inspection an the ease of parts replacement are escribe in Loabuster Instruction Sheet Limitations on Use 1. Loabusters must be use only with isconnects, cutouts, power fuses, fuse limiters, or ropout reclosers which meet S&C s applicable minimum construction specifications foun in the current revision of Data Bulletin Loabuster Catalog Number 5400R3, rate 25/34.5 kv, must not be use with metal-enclose switchgear, metal-enclose switches or fuses, or pa-mounte gear, of any make. 3. Although the interrupting ratings of Loabuster Catalog Number 5400R3, rate 25/34.5 kv, are equally applicable at lower voltages, it must not be use with the following evices, since the fuse tube or blae travel of such evices is too short to accommoate Loabuster s operating stroke: (a) Cutouts, power fuses, fuse limiters, or ropout reclosers of any make, rate 110 kv BIL or less; (b) Disconnects, cutouts, power fuses, fuse limiters, or ropout reclosers of any make, rate 7.2/14.4 kv, 7.8/13.8 kv, 8.25 kv, or less; (c) Disconnects of any make, rate 125 kv BIL or less; () Discontinue Station Style S&C Type XS Fuse Cutout Catalog Number (with or without catalog number supplements). 4. Loabuster must not be use in applications where maximum system operating voltage excees the Loabuster s maximum voltage rating. 5

6 Switching with Loabuster Is Easily Learne... It s as Easy as One-Two-Three Loabuster is light in weight an simple to operate. It enables you to open isconnects, cutouts, power fuses, fuse limiters, an ropout reclosers quickly an easily. Just position Loabuster across the front of the evice, with the tool s anchor place on the attachment hook on the far sie of the evice. Engage Loabuster s pull-ring hook on the pull-ring of the blae or fuse tube; it s hel fast by the tool s pull-ring latch. As the universal pole is pulle ownwar with a firm, steay stroke an Loabuster is extene to its maximum length the evice is opene; current is simultaneously iverte through Loabuster... at the same time Loabuster s internal operating spring is charge. At a preetermine point in Loabuster s operating stroke, its internal trigger trips, the charge operating spring is release, internal contacts are separate, an the circuit is positively interrupte. The only soun is that of Loabuster tripping. Circuit interruption is inepenent of the spee with which Loabuster is operate. All that s require is a smooth operating stroke, without hesitation or jerking... until the tool is extene to its maximum length. The resetting latch retains the tool in the open position for removal from the evice an until release to reset Loabuster for its next operation. Resetting Loabuster is easy too. Release the resetting latch an firmly close the tool to its fully telescope position until the orange ban on the inner tube assembly is no longer visible. Then exten the tool about three inches an let it snap back to verify spring tension. NOT RESET RESET Switching a Disconnect f Switching a Fuse Cutout a, Power Fuse, Fault Tamer Fuse Limiter, or TripSaver Dropout Recloser 1 Attach Reach across the front of the evice an attach Loabuster s anchor to the attachment hook on the far sie. Then engage the evice s pull-ring with Loabuster s pullring hook. Loabuster s pull-ring latch prevents inavertent isengagement of the pull-ring an pull-ring hook. 2 Pull A firm, steay ownwar pull on Loabuster to its maximum extene length opens the evice in the normal manner, as the current is iverte through Loabuster. At a preetermine point in the opening stroke, Loabuster trips, breaking the circuit positively. 3 Roll Off Loabuster is isengage by first removing its anchor from the evice s attachment hook. Then, with the blae or fuse tube in the fully open position, Loabuster is remove from the pull-ring with a simple roll-off motion. f 34.5-kV Crossarm Inverte Style S&C Loabuster Disconnect shown. a 25-kV Ultra-Heavy-Duty Overhea Pole-Top Style S&C Type XS Cutout shown. 6

7 This Is How Loabuster Works 1 Loabuster Provies a Current Path between the upper contact an the pull-ring of the isconnect, cutout, power fuse, fuse limiter, or ropout recloser, as inicate by the soli re line. Note the points of similarity to the interrupting unit of a conventional loa-interrupting evice: the moving contact, stationary contact, arc-extinguishing chamber, an trailer. 2 When Loabuster Is Extene by a firm, steay ownwar pull on the universal pole, the isconnect, cutout, power fuse, fuse limiter, or ropout recloser is opene; the current is iverte through the tool (along the current path represente by the soli re line); an the internal operating spring is charge. At a preetermine point in the opening stroke, the trigger insie the tool trips, releasing the charge spring to effect high-spee separation of the moving contact from the stationary contact. 3 The Current Is Positively Interrupte by rapi elongation of the arc confine within the arcextinguishing chamber, in the narrow annular space forme between the trailer an the liner an by the efficient eionizing action of the gases yiele by the surrouning materials of the trailer an the liner. In the maximum extene position, picture here, an isolating gap is establishe (where the broken, shae re line is parte) within the arc-extinguishing chamber. The resetting latch retains the tool in this open position until release to reset Loabuster for its next operation Loabuster s pull-ring hook makes mechanical an electrical connection with pull-ring of evice being switche Loabuster s anchor makes mechanical an electrical connection with attachment hook on upper contact of evice being switche Resetting latch Trailer Spring Moving contact assembly Loabuster s pull-ring latch prevents pull-ring hook from inavertantly isengaging evice s pull-ring Stationary contact assembly Arc-extinguishing chamber Trigger Liner 7

8 Selecting a Disconnect, Cutout, Power Fuse, Fuse Limiter, or Dropout Recloser Here s what to look for when selecting a isconnect, cutout, power fuse, fuse limiter, or ropout recloser to be switche with Loabuster: h There must be an attachment hook at the upper (jaw) en of the evice, over which Loabuster s anchor can be hooke; an a pull-ring on the evice s switch blae or fuse tube which can be reaily engage with Loabuster s pull-ring hook an hel fast by the pull-ring latch. h The evice must mechanically coorinate with Loabuster s operating sequence such that (a) engagement of Loabuster will not cause or allow the switch Quantitative Requirements for Devices Qualifying for Use with Loabuster blae or fuse tube to rop open prematurely an (b) the attachment hook will keep Loabuster positively anchore until tripping occurs, while (c) permitting easy removal of Loabuster whether the opening stroke has been complete or whether, for any reason, the evice being switche has been reclose after partial (incomplete) opening. h The evice must be capable of easy, positive manipulation with Loabuster from all practical angles an irections an in all mounting positions intene or the evice while maintaining the minimum mechanical an electrical requirements, as liste in the table below. I II III1 IV6 V7 Loabuster Catalog Number Disconnect, Cutout, Power Fuse, Fuse Limiter, or Dropout Recloser Application Max System Operating Voltage, Three-Phase Minimum Dry Withstan Voltages Across External Disconnect Gap2 60-Hertz3 at Time of Tripping4 Capacitance Switching Test5 Circuit Voltage Suggeste Minimum External Disconnect Gap Separation2 at Time of Tripping4 Suggeste Minimum External Disconnect Gap Separation2 with Loabuster Fully Extene to Latche-Open Position kv kv, RMS kv, RMS Inches (mm) Inches (mm) 5300R ¹ ₂ (89) 4 (102) 5300R3 & 5400R ¹ ₂ (89) l 3⁷ ₈ (99) 4¹ ₂ (115)l 5 (127) 5300R3 & 5400R ⁷ ₈ (99) 5 (127) 5300R3 & 5400R l l 27 3⁷ ₈ (99) 4³ ₄ (121) 5 (127)l 6 (153) 5400R3 29 a 29 5¹ ₄ (134) 6¹ ₂ (166) 5400R3 38 a 29 5¹ ₄ (134) 6¹ ₂ (166) 1 Disconnects, cutouts, power fuses, fuse limiters, or ropout reclosers (while being switche with Loabuster) must be capable of withstaning at least one of these tests without flashover, preferably with the mounting bracket or base of the evice uner test groune. However, in the case of evices with insulation just meeting minimum ANSI stanars, it may be necessary to test with mounting bracket or base floating. The specifie voltages are given for stanar atmospheric conitions of temperature, barometric pressure, an humiity, an must be correcte for the existing atmospheric conitions at the time of test. 2 Between all live parts of the combination of Loabuster an isconnect, cutout, power fuse, fuse limiter, or ropout recloser for the most unfavorable practical operating position of Loabuster. 3 These minimum voltages must be applie for a perio of 10 secons. The voltage shall be applie starting at 75% of the ultimate value an raise to the liste test voltage at a constant rate such that the test voltage is reache in not less than 5 secons nor more than 10 secons. An appropriately calibrate means must be use to measure the voltage. 4 Trippe conition is simulate when Loabuster Catalog Number 5300R3 is telescope to 1⁷ ₈ inches (48 mm) from latche-open position, or when Loabuster Catalog Number 5400R3 is telescope 1³ ₈ inches (35 mm) from latche-open position. 5 This test consists of interruption of a 0% PF leaing capacitance current of 2 to 5 amperes with Loabuster use in the most unfavorable operating position. The test circuit is to be energize by a 60-hertz source at the voltage specifie. A test series of 20 successive operations must be performe without flashover across the external isconnect gap. 6 These imensions are approximately those require to meet the voltages specifie in Column III. They are base on esigns where sharp points, sharp eges, protrusions, etc., are avoie so that essentially ro-gap configuration is obtaine on isconnect, cutout, power fuse, fuse limiter, or ropout recloser contacts. Sharp points, eges, etc., may require minimum gaps measuring as much as 25% greater than the imensions liste to achieve the same ry withstan values. 7 These imensions permit Loabuster to be remove without reucing the gap below the values liste in Column IV, an shoul be maintaine after circuit interruption (even though the transient recovery voltage may not then be a factor) to provie margin for possible inattentive manipulation of Loabuster. l Loabuster Catalog Number 5300R3. Loabuster Catalog Number 5400R3. a Loabuster shoul not be subjecte to sustaine 60-hertz voltage of the value that woul be require for this test. Only the Capacitance Switching Transient test (column at right) is applicable at this voltage. S&C ELECTRIC COMPANY Specialists in Electric Power Switching an Protection Offices Worlwie Telephone: (773) Fax: (773) Printe in U.S.A.