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GEH2621A Instructions AV - Line Switchboards Installation and Maintenance n- - Elicit if I # EaGB : s mm- * O B - . : #> £& I i i\ WP - if . H > ; * I > 3 i < . # T " - i | * T * 9 9 1 GENERAL ^ ELECTRIC

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  • GEH2621AInstructions

    AV-LineSwitchboardsInstallation andMaintenance

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    G E N E R A L^E L E C T R I C

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  • Table of Contents

    PAGEDESCRIPTIONAV-LINE Switchboard ConstructionReceiving, Handling and StorageInstalling the Bus Stub

    For LVD StubsFor Armor Clad Stubs

    Short Circuit Cable BracingMAIN CABLE

    AV-1, AV-2, AV-5 Switchboardsutilizing cord for Short Circuit Protection.AV-3, AV-4 Switchboardsutilizing cord for Short Circuit Protection.

    LOAD CABLEAV-3, AV-4 Switchboardsutilizing cord for Short Circuit Protection.

    Installing the SwitchboardSwitchboard Maintenance

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  • AV-Line® SwitchboardConstructionThese instructions do not purport to cover ail de-tails or variations in equipment nor do they pro-vide for every possible contingency to be met inconnection with installation, operation or mainte-nance. Should further information be desired, orshould particular problems arise which are notcovered sufficiently for the purchaser’s purpose,the matter should be referred to the GeneralElectric Company.

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    FIGURE 1Typical group mounteddistribution construction.

    FIGURE 2Typical individuallymounted distributionconstruction.

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  • Receiving, Handling and StorageRECEIVING

    45° MINIMUMBefore leaving the factory, the switchboard is given a final in-spection and packed by workmen experienced in the properhandling and packing of electrical equipment. Upon receipt ofany apparatus, an immediate inspection should be made for anydamage sustained in transit. If damage is noted, or indication ofrough handling is visible, a claim for damage should be filed withthe carrier. Information as to damaged parts, part number, casenumber, requisition number, etc., should accompany the claim.Inregard to claims for damagedshipments,shortages and incor-rect material, the following is an excerpt from the PublishedSupplemental Terms and Conditions of Sale for products of theDistribution Equipment Division, General Electric Company.“Title and risk of loss shall pass upon delivery of the products tothe carrier at the f.o.b. point and invoices shall be payable with-out deduction for losses in shipment. It is the Purchaser’s re-sponsibility to file claims with the carrier for loss or damage intransit.”

    -

    “Claims for shortages or incorrect material must be made inwriting within 30 days after receipt of the shipment by the Pur-chaser, and the failure to give the Company such written noticewithin the 30-day period shall be unqualified acceptance of theproducts and a waiver by the Purchaser of all claims for short-ages or incorrect material.”

    HANDLING FIGURE 4FIGURE 3Using lifting slings, spreader Using lifting plates, angles orand blocking are not furnished beams which are furnished

    with equipment.

    Equipment may bemoved into positionby means of constructionrollers under the shipping skids. Remove all outer packaging.Lifting by crane or other hoisting methods done as shown inFigures 3 and 4.To remove the AV-LINE Switchboard from the skids after takingout the shipping bolts, carefully slide the equipment so that therear side is off the skids, resting on the floor (see Fig. 5). Tit theentire equipment slightly to the rear to release the skids. Cautionis advised in sliding and tilting this equipment due to its heightand weight. It can become top heavy if tilted too far. Slide theswitchboard into place by pushing on the frame. Blow out anydust or loose particles of packing material which may have col-lected on the device parts. Remove all protective blocking onrelays, devices or breakers.

    with equipment.

    LIFTING INSTRUCTIONS1. Do not pass cables or ropes through support holes.2. Always use load rated shackles or safety hooks in support

    holes.3. Rig so that legs of sling (Figs. 3 and 4) are no less than 45°

    from horizontal.

    REMOVE

    STORAGE 1X -/If it isnecessary to store the equipment for any length of time, the

    following precautions should be taken to prevent corrosion orbreakage:1. Uncrate equipment.2. Store in a clean, dry, rodent-free area in moderate tempera-

    ture. Cover with a suitable canvas to prevent deposits of dirtor other foreign material on movable parts andelectrical con-tact surfaces. (Heavy duty plastic coversare recommended.)

    3. If stored in cool or damp areas, heat should be provided tokeep the equipment dry. On outdoor switchboards this maybe accomplished by making a temporary power connectionto the heaters installed in the equipment. On indoor switch-boards, two standard120 volt lamps ratedat 100wattscanbeused inside each vertical section.

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    REMOVE

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    FIGURE 5Remove lag bolts. Slide unit off skid and remove skid.CAUTION

    : Remove all cartons and other miscellaneous pack-ing material from inside the units before energizing any heaters.

    4

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  • Installing The Bus StubSTUBSTUB 1

    2 3STUBCOVER

    STUBCOVER

    FLANGEADAPTER 6

    REMOVABLEFRAMEMEMBER

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    r aREMOVEREARCOVER

  • WARNING:Short Circuit Cable Bracing Required s: \LOAD CABLE BRACINGMAIN CABLE BRACINGLoad cable short circuit bracing is required for each componentinstalled in an AV-3 or AV-4 switchboard section with availableshort circuit currents of 65,000 rms symmetrical amperes andabove.

    Maincablebracingisrequiredwhenfivecablesperphase or lessfeed a switchboard at available short circuit currents of 100,000and 150,000 rms symmetrical amperes, and eight cables perphase or less at an available short circuit current of 200,000 rmssymmetrical amperes.Assembly, purchasing and maintenance instructions for maincable short circuit bracing can be found on pages 6 and 7.

    Assembly, purchasing and maintenance instructions for loadcable short circuit bracing can be found on page 8.

    Installing The Main CableAV-1, AV-2 AND AV-5 SWITCHBOARDS UTILIZING CORD FOR SHORT CIRCUIT PROTECTION

    PRIOR TO INSTALLATION minimum, making 6 revolutions around the "A” and “B,? phase

    main cables and 6 revolutions around the “B" and “C” phasemain cables.Now, with the remaining cord, wrap the main cablelashing to the cable braces in between phases with 4 to 5 revolu-tions, tieing a knot to the cable braces as you complete your lastrevolution. All revolutions shouldbe made as tight as possible soas to prevent whipping during short circuits.

    Before any installation work is performed, study all drawingsfurnished by the General Electric Company for the particularinstallation. These include arrangement drawings (front, endand plan view), connection diagrams and schedule of equip-ment. Any material external to the equipment which may berequired to meet any local codes (railings, etc.) is not furnished.

    INSPECTION AFTER MAIN CABLEINSTALLATION

    CABLE BRACE4To prevent heating, there should be no closed loop of steelarounda singleconductor or group of conductors whichdoesnotinclude all the conductors (including the neutral) of the circuit. Ifthe conductors must pass through separate holes in a piece ofsteel,slots shouldbe cut between the holes. Do not allow cablescarrying heavy current to come near instruments or meters asthis may affect their accuracy.Use the minimum amount of cablenecessary to accomplish the connections.The increasedresist-ance of longer cables generates unnecessary heat.Main cablelashing should be checked bi-monthly.

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    MAIN CABLE TERMINALS

    FIGURE 7B

    INSTALLATION PROCEDURES FORMAIN CABLE WITH SHORT CIRCUITPROTECTIONAlignconduit holes in a linear orientation directly over or as closeas possible to the braces. Consideration should be given toinstalling conduits or sleeves which might be required for futureconnections.Run and bend the main cable in a most convenient orientation,making sure the main cable has been located directly up againstthe cable braces before it connects to the main cable terminals.Lash the main cable according to Figure 7B above, using apolyester braided rope having a tensile strength of 2000 lbs. )

    6

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  • Installing The Main Cablef AV-3, AV-4 SWITCHBOARDS UTILIZING CORD FOR SHORT CIRCUIT PROTECTION

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    CABLE BRACE

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    FIGURE 7C FIGURE 7D

    PRIOR TO INSTALLATION INSPECTION AFTER MAIN CABLEINSTALLATIONBefore any installation work is performed, study all drawings

    furnished by the General Electric Company for the particularinstallation. These include arrangement drawings (front, endand plan view), connection diagrams and schedule of equip-ment. Any material external to the equipment which may berequired to meet any local codes (railings, etc.) is not furnished.

    To prevent heating, there should be no closed loop of steelarounda single conductor or group of conductors whichdoes notinclude all the conductors (including the neutral) of the circuit. Ifthe conductors must pass through separate holes in a piece ofsteel,slots shouldbe cut between the holes. Do not allow cablescarrying heavy current to come near instruments or meters asthis may affect their accuracy.Use the minimum amount of cablenecessary to accomplish the connections. The increased resis-tance of longer cables generates unneccessary heat. Main ca-ble lashing should be checked bi-monthly.

    INSTALLATION PROCEDURES FORMAIN CABLE WITH SHORT CIRCUITPROTECTIONAlign conduit holes in a linear orientation a distance equal to theradius bend of the cable. Consideration should be given to in-stalling conduits or sleeves which might be required for futureconnections (see Figure 7D). Run and bend the main cable in amost convenient orientation, making sure the main cable hasbeen located directly up against cable braces before it connectsto the main cable terminals (see Figure 7C). Lash the main cableaccording to Figure 7C above, using a polyester braided ropehaving atensile strength of 2000 lbs.minimum, making 6 revolu-tions around the “A” and “B” phase main cables and 6 revolu-tions around the “B” and “C” phase main cables. Now with theremainingcord, wrap the maincable lashing to thecable brace inbetweenphaseswith4to5revolutions,andtieaknot to thecablebrace as you complete your last revolution. All revolutionsshould be made as tight as possible so as to prevent whippingduring short circuits.

    7

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  • Installing The Load Cable•V

    AV-3 AND AV-4 SWITCHBOARDS UTILIZING CORD FOR SHORT CIRCUIT PROTECTION • I

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    FIGURE 7FFIGURE 7E

    INSPECTION AFTER LOAD CABLEINSTALLATION

    PRIOR TO INSTALLATIONBefore any installation work is performed, study all drawingsfurnished by the General Electric Company for the particularinstallation. These include arrangement drawings (front, endand plan view), connection diagrams and schedule of equip-ment. Any material external to the equipment which may berequired to meet any local codes (railings, etc.) is not furnished.

    To prevent heating, there should be no closed loop of steelarounda single conductor or group of conductors which doesnotinclude all the conductors (including the neutral) of the circuit. Ifthe conductors must pass through separate holes in a piece ofsteel, slots shouldbe cut between the holes. Do not allow cablescarrying heavy current to come near instruments or meters asthismay affect their accuracy. Use the minimum amount of cablenecessary to accomplish the connections. The increased resis-tance of longer cables generates unnecessary heat. Loadcablelashing should be checked bi-monthly.

    INSTALLATION PROCEDURES FORLOAD CABLE WITH SHORT CIRCUITPROTECTIONLocate the load cable braces which can be found every 18" onthe back of the switchboard. Run and bend the load cable in themost convenient manner, making sure that the load cable is upagainst the load cable brace closest to the component’s loadterminals(see Figure 7E) andto every loadcable brace above orbelow, dependingif the loadcable will exit the switchboard on topor bottom (see Figure 7F).After running the loadcable up against the loadcable bracesandusing apolyester braided rope having a tensile strength of 2000lbs.minimum,lash the loadcable to the loadcablebrace,making4 revolutions around the cable and the brace. Tie a knot to thecablebrace after completionof the last revolution. All revolutionsshould be made as tight as possible so as to prevent whippingduring short circuits.

    8

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  • Installing The AV-Line SwitchboardPRIOR TO INSTALLATIONBefore any installation work is performed, study all drawingsfurnished by the General Electric Company for the particularinstallation. These include arrangement drawings (front, end,and plan view), connection diagrams and schedule of equip-ment. Any material external to the equipment which may berequired to meet any local codes, (mats, screens, railings, etc.),is not furnished. gn,

    nuLOCATIONIn locating the switchboard, consideration shouldbe givento theaisle space required.The space at the front must be sufficient topermit the opening of doors, and the insertion and withdrawal ofremovable breakers. The space at the rear must be sufficient foropening of doors as well as the cables, inspection, and mainte-nance. Check local codes for special aisle space requirements.

    FIGURE 8Bolting the switchboard directly to the floor—

    indoor construction.FRONT

    \FOUNDATION REQUIREMENTSIndoor Equipment—The floor or foundation must be strongenough to prevent sagging from the weight of the switchboardstructure. If the foundation is subject to vibrations, specialmounting must be provided to prevent the transmittal of vibra-tions to the equipment.Becauseof itshighstructuralstrength,theAV-LINESwitchboardmay be bolted directly to the floor (see Fig. 8). The floor must beentirely level without any high spots whichmight cause misalign-ment. If the floor isnot levelit is recommendedthat floor channelsbe used.The steel floor channels when used should be embedded in alevelconcrete slab with the top surface of the channels flush withthe finished floor. To avoid distortion of the structure, it is essen-tial that the steel channels be level and aligned with each otherprior to the final anchoring. The recommended foundation con-structionandmethodof mounting the switchboard to the founda-tion is shown in Fig. 9. Channels should be grouted afterinstallation.

    iur rFIGURE 9

    Switchboard mounted on floor channels—indoor construction.FRONT\j

    IOutdoor Equipment—Outdoor equipment is usually installedon a concrete pad with a level and smooth surface. Channel sillsare supplied with the switchboard, two with the non-walk-in typeand three for the walk-in type as shown in Figs. 10 and 11.Channels should set on the pad and be filled with grout.Conduits—At the time the foundation channels are being in-stalled, any conduits or sleeves required for power and controlcables that are to enter the equipment from underneath shouldbe located and installed within the available space shown on thefloor plan drawings. Consideration should be given to installingconduits or sleeves which might be required for future connec-tions.Conduitstubsshouldextendabove thefloor just enoughtoprevent the entrance of water.Consideration should be given tothe locationof components in the switchboard and space shouldbe allowed for swinging cables after they leave the conduit.Thelowest live metalpart in the switchboard will be approximately 8"minimum above the bottom of the switchboard (not includingfloor sills). It should be noted that the switchboard must be liftedover the conduit stubs. The conduits should terminate at theswitchboard with the appropriate conduit connectors. Conduitsmay require grounding or electrical connection to the switch-board enclosure.

    I f1%"zFIGURE 10

    Non-walk in type switchboard—outdoor construction.FRONT

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    FIGURE 11Walk-in type switchboard—outdoor construction.

    9

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  • Installing The AV-Line Switchboard3-PHASE 4 WIRE SUPPLY

    N G . V1 2 3© L©SERVICE

    ENTRANCEMAIN BREAKER ) ) )FIELD CONNECTIONS AND TESTING OF

    GROUND-FAULT PROTECTION SYSTEMS(7) In the service-entrance section, the neutral conductor shall

    be bonded to the switchboardgroundbus by a“mainbondingjumper” (ground strap) (NEC 250-5;UL-891, Para. 23.8 and23.12).Thisgroundingpoint on the neutral conductor shallbelocated on the supply side of any ground-fault sensors in-volving the neutral conductor (UL-891,Para. 15.4 and 15.5).Grounding connections shall not be made to the neutral con-ductor on the load side of the service disconnecting means(NEC 250-23a;UL-891, Para. 15.4).

    (?) On load feeders, run all phase conductors (and neutral ifused) through the sensor window(s), with all in the samedirection with respect to sensor polarity.

    (J) Do not run equipment ground conductors through ground-fault sensors. Connect them directly to the switchboardground bus (not to the neutral bus) (UL-891, Para. 38.39).

    (71) Connect the service grounding electrode (water pipe, etc.) tothe lug provided on the switchboard ground bus for this pur-pose (NEC 250-26c; UL-891,Para. 23.6).

    (J) Whenever a service is derived from a grounded neutral sup-ply, the grounded neutral conductor must be brought into theservice-entrance equipment, even if thegrounded conductoris not needed for the load supplied by the service (NEC 250-23b). This is required to provide a low-impedance ground-fault current return path to the neutral to assure operation ofthe overcurrent device, for safety to personnel and property.

    (&) Refer to GEI-48907 for instructions for conducting perfor-mance tests of new installations of ground-fault protectionsystems, as required by NEC 230-95(c).

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    & ;T) ) ) ) ) )FDR ¥ 1 FDR #2iE- yi IGF = INTEGRAL GROUNDFAULT PROTECTION3 WIREIGF GHDr̂r 8US©y V ''t 1 2 3 ' ' © 'i' V V2 3.N vj. ©v V

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    TYPICAL SINGLE-SOURCEGROUND FAULT PROTECTION

    USING INTEGRAL GROUND FAULT TRIPS

    FIGURE 13

    FUSE SELECTIONThe proper fuses for each circuit should be selected based on loadcharacteristics (see Ambient Temperatures and Circuit Loading) andavailable short-circuit current at the line terminals of the switchboard.Select a fuse for which the rating of the combination fuse and switchequals or exceeds the available short-circuit current. Removable link-type fuses are not recommended.

    TESTING AND INSPECTIONAfter the equipment hasbeen installed and allconnections made, it shouldbe testedandinspected BEFOREENERGIZING. Althoughthe equipmentand devices have been inspected at the factory, a final field test should bemade to be certain that the equipment has been properly installed and thatall connections are correct and have not become loose in transportation. Itisrecommended that the switchboardbe completely wire checked, and allbolts and terminals double checked for tightness. Check all Kirk keyinterlocking schemes to insure desired performance. The incoming lineshould be completely de-energized while the tests are in progress.In addition to these mechanical checks the switchboard should bemeggered. Meggering should be performed with all switchboard devicesin the open position and all instrumentation and control fuses removed. Amegger(megohmmeter) developing 500 volts should be used. As a guideswitchboards tested when leaving the factory have shown typicalminimum values of 100 megohms. Any switchboards job tested under theabove conditions showing values considerably below this should beinspected for possible tracking on insulation or insulation breakdown.All scraps of wire, plaster, dust and other foreign material must beremoved. Vacuum cleaning is the recommended method of removal.After thorough cleaning and inspection, if the megger reading is still low,it may still be safe to energize the equipment. When restoring flooded orwet equipment to service, for example, it is accepted maintenance prac-tice to require a minimum of one megohm before energizing. Underdamp or humid conditions it is considered good practice to operate theequipment at lower-than-rated voltage for a short time, if possible, toimprove the low megger reading.Instructions for inspection and testing of low voltage power circuit \breakers are given in the applicable individual instruction book. Direc-tions for testing devices such as relays, instruments and meters aregiven in the instruction book furnished for each device. Protective relaysmust be coordinated with other relays in the system, therefore theserelays are to be set by the purchaser. General instructions on setting therelays are given in the relay instruction books.

    3-PHASE4 WIRESUPPLY

    1 2 3 N GALTERNATE SENSOR

    ARRANGEMENTS

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    ALTERNATE SENSORSFOR MAIN BREAKER GFP c X> t© I

    ZEROSEQUENCEGROUND

    RETURNSENSOR) )SERVICEENTRANCE

    MAIN BREAKER

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    x>-(( I IZERO-SEQUENCE ORRESIDUAL SENSOR RESIDUAL

    2 3 NNEUTRAL NBUS

    (X X X^IRESIDUAL1 !>~Epl) ) >-- ) ) ) GFR - GROUND FAULT RELAYFDR 01 GFR FDR 02 GRDc sus

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    TYPICAL SINGLE-SOURCEGROUND FAULT PROTECTION

    USING GROUND FAULT RELAYS

    FIGURE 1210

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  • GROUND FAULT PROTECTIONWhen ground fault protection is furnished, it is important that all field connections shall be madecorrectly so that the ground fault protection system will function properly. Observe the following rules,illustrated in Figs. 12, 13.

    ELECTRICAL CLEARANCESBOLTINGThe followingminimumclearances shouldbe maintainedexceptat terminals of circuit breakers and switches:

    AV-Line switchboards are furnished with medium carbon steelhardware having a high tensile strength. V4" to Vs" bolts have atensile strength of 120,000 psi, and W to 5/s" bolts have astrength of 60,000 psi. Similar hardware should be used for anyadditional bolting. The use of a torque wrench is recommendedto assure the following torques. These torques apply to alumi-num or copper connections. When torquing bolts the followingvalues are nominal:

    0-125V 126-250V 251-600VBetween live parts of oppositepolarity:

    Through airOver surface

    Between l i ve par ts andgrounded metal through air orover surface

    GROUNDINGWhere required, the groundbusisbolted tothe uprights of the rearframe structure. It is arranged so that connections to the stationground can be made in any unit. A ground lug is included in eachcomplete equipment for tying the switchboard to the stationground. IT IS VERY IMPORTANT THAT THE EQUIPMENT BEADEQUATELY GROUNDED,TO INSURE THATALL PARTS OFTHE EQUIPMENT, OTHER THAN LIVE PARTS, ARE ATGROUNDPOTENTIAL.Groundsensor relays are recommendedfor protection of the switchboard.

    V2" 3/4" 1"2"3/4" 11/4"

    8-10 lb. ft.16-19 lb. ft.23-27 lb. ft.35-40 lb. ft.45-50 lb. ft.

    1/4" — 20 bolts5/i6 w — 18 bolts

    — 16 bolts1/2" — 13 boltss/s" — 16 bolts

    Flat washers and spring washers should be used for all connec-tions. Washers should not be included under the heads of car-riage bolts.

    V2" V2" 1"

    Switchboard MaintenanceCAUTION! De-energize this equipment before performing any work.A periodic maintenance schedule should be established to ob-tain the best service from the switchboard. An annual check andoverall maintenance procedure for the switchboard devices andall connections, should be followed as a minimum requirement.Equipment subject to highly repetitive operation may requiremore frequent maintenance.A permanent recordof allmaintenance work shouldbekept. Therecord should include a list of periodic checks and tests made,the date they were made, the condition of the equipment, andany repairs or adjustments that were performed. Maintenanceemployees should follow all recognized safety practices, suchas those contained in the National Electrical Code, OSHA and incompany or other safety regulations during maintenance.For specific information regarding the maintenance of devices,such as circuit breakers, relays, meters, etc., refer to the sepa-rate instruction book furnished for each device.1. Periodically inspect switchboard, while under load to deter-

    mine if there is any indication of overheating. If overheatingorany other unsatisfactory condition is found, completely de-energize switchboard and investigate. Particularly look forloose bolts and connections, or overloading. Remove anyaccumulation of dirt or other foreign matter in enclosure. Donot touch live parts while switchboard is energized.

    2. Plated parts may become dark over a period of time due tooxidation. Do NOT remove this discoloration, as it will reducethe thickness of the plating.

    3. Retighten lugs and joints to eliminatepossibleheatingpoints.Transmittal of vibration throughbuilding structure andconduitto switchboard may loosen lugs and joints. Turning load offand on causes expansion and contraction between lug andcable tending to loosen lug.

    4. Do not opensealed breaker or trip units as calibrationmay bedisturbed. Return to factory for any replacement.

    AMBIENT TEMPERATURES ANDCIRCUIT LOADINGSwitchboards are designed for installationwhere average ambi-ent temperature will not exceed 40°C (104°F). For higher tem-pera tu res, dera t ing may be requ i red. The conduc to rtemperatures within the enclosure may be as high as 80°C(176°F). Some parts of breakers, switches and fuses may runhotter. In accordance with NEC Art.384-16(c) it is recommendedthat thermal-magnetic molded-case breakers in switchboardsnot be loaded in excess of 80% of rating where load will continuefor three hours or more, even with ambient-compensatedbreakers.

    SHORT CIRCUITSNormally, the overcurrent protective device on the circuit willprevent any electrical damage except at the actualpoint of short-circuit. A thorough inspection of the entire system after any largefault current should be made to insure that there has been nomechanical damage to conductors, insulation or equipment.In addition, the individual overcurrent protective device or de-vices which performed the short-circuit interruption must be in-spected for possible arcing damage to contacts, arc chutesand/or insulation. Do not open sealed devices such as breakertrip units or 150A frame breakers. If there is any possibility thatsealedunits may have been damaged, they should be replaced.For additional details on the particular device involved, refer tothe applicable individual instruction book.

    ARCING DAMAGE TO INSULATIONSome organic insulating materials carbonize when subjected tothe heat of an electrical arc and lose their insulating qualities.Any insulation found to be carbon-tracked must be replacedbefore applying power.

    (Continued on Page 12)

    11

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  • Switchboard MaintenanceWATER-SOAKED EQUIPMENT1. Completely de-energize switchboard.2. Carefully clean and dry all parts of the switchboard. When

    using heaters, do not exceed 180 degrees F.3. Replace all fuses.4. Individual devices should be inspected for the possible en-

    trance of water, dirt or foreign matter.5. Do not open sealed devices such as breaker trip units or

    150A. frame breaker. Replace them.6. Prior to re-energizing the switchboard it shouldbemeggered.

    Refer to testing and inspection section on page 10 .7. If assistance or guidance is required contact your local Gen-

    eral Electric service engineer. General Electric ServiceShops have facilities for reconditioning.

    SPARE PARTSA spare parts stock for the components of the AV-Line Switch-board, such as bus, insulators, etc. is not recommended. Whencomponents needtobereordered,pleaserefer to thenameplatemarking, shop drawing number, and order by description. Aspare parts stock of devices such as circuit breakers, meters,switches, etc. will vary due to the variety of installations. YourGeneral Electric Sales Engineer will be glad to assist you in theproper selection for a device stock list.

    For further informationcall or write your localGeneral ElectricSales Office o r . . .

    Distribution EquipmentDivision41 Woodford AvenuePlainville, CT 06062

    isV

    E L E C T R I CG E N E R A LGEH2621A 4/81 10M

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