Transfer Switch accessory poles (2 or 3) DIAGRAMS ....back of manual provided rating ASCO Service Centers ..inside back cover ampere (30-4000) control panel code 8 for single phase Only experienced licensed electri for three phase A DANGER cians should install the switch.
SECTION INSTALLATION ASCO automatic transfer switches are factory wired and panel are usually supplied on mounting rails. Refer to the tested. Field installation simply requires mounting and Composite Outline and Mounting Diagrams for details. connection of service cables, engine start signal wires, and auxiliary control circuits (if required).
INSTALLATION (continued) left side Connect source and load conductors to clearly marked CllT AC TS of switch switch terminal lugs. Be careful when stripping insulation us. STlITlII , I ..II-U .. ''''., from cables; avoid nicking or ringing the conductor. Re move surface oxides from cables by cleaning with a wire brush.
INSTALLATION (continued) Functional Test T he Functional Test consists of three checks: manual op eration, voltage checks, and electrical operation. CAUTION: Do these checks in the order presented to avoid damaging the switch. Read and understand all instructions on the Composite Elementary Wiring Diagrams and on labels affixed to the automatic transfer switch.
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(up to 30 minutes). 6. Shut down the engine-driven generator. Then put the starting control selector switch (on the generator This completes the Functional Test of the ASCO 940. The set) in the automatic position. engine-driven generator's starting control should be left in the automatic position.
SECTION SEQUENCE OF OPERATION Composite Elementary Wiring Diagram. See the Note any Optional Ac cessories that may be furnished on this switch, and review their operation. Refer to any separate drawings and/or publications that may be packed with this switch. Transfer To Emergency The transfer switch will remain in the Emergency position until the normal source is restored.
These are factory settings. Refer to the problem is isolated to circuits on the control panel or the transfer switch, call your local ASCO Authorized Repre sentative, District Office, or Service Center. Furnish the Serial No. and Catalog No. from the transfer switch nameplate.
SECTION ADJUSTMENTS Time Delay Adjustment incremental. Two DIP switches are used; each has eight actuators. See Figures 4-2,4-3, and 4-4 on page 4-2. Features 1, 2B, 3A, and 2E time delays are factory set to the job specifications. Unless otherwise specified, the standard factory setting is used.
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ADJUSTMENTS (continued) IIII III I I 1111 11111111 11111111 I 111111 Figure 4-1 . Standard factory settings. The template in Figure 4-1 above shows the standard fac tory settings for the DIP switches on the upper circuit board (13) of the control panel. WARNING: D o not make any setting changes while the control panel is energized.
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ADJUSTMENTS (continued) Chart 1 Chart 2 11111111 Retransfer to Normal Time Delay Override Moment ary Outages Time Delay 12345678 Faoture 3A Feature Actuotor PosItIons Deloy AcTuator PosItIons TIme Daloy SWItch SwItch SellIng SetTIng y[illL "fJill] o seconds o seconds off' 1234 5678 of f...
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ADJUSTMENTS (continued) Chart Chart 111 .. 1 .. Transfer to Emergency Time Delay Gen-Set Cool Down Time Delay 12345678 Fealu,.e ACTuator Po� 1 01'10; Fealu,.e 28 Actuator PosItIons TIme Deloy TIme Oela)' ° f lmJ SettIng SettIng SwItch ° f [iiiL SwItch o seconds 0 mInutes...
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ADJUSTMENTS (continued) Chart 5 Chart 11111111 Emergency Source Voltage Pickup 12345678 Normal Source Voltage Pickup voltags Poslttons Actuator- PO&tTton& voltage Actuator- pIckup & pIckup SWItch .. ettlng SWItch settIng percent °filliL ylmJ of f 85 percent 1234 5678 o rf 86 percent 86 percent 1234...
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ADJUSTMENTS (continued) Chart 7 4 7 ) (see page 11111111 Normal Source Voltage Dropout Normal Source Voltage Dropout (continued) 1234�678 (percent of pickup setting) (percent of pickup setting) tag .. Actuator Poet lton .. vottage Actuator Poeltlone •• •• SwItch dropout dropout ttln;...
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ADJUSTMENTS (continued) How To Determine the Normal Source Voltage Dropout Setting (% Pickup) (shown in Chart on page 4-6, based on a percentage of Nominal) 1. D etermine the Normal Source Voltage Pickup Setting as set on DIP Switch S3 (actuators 5-8) in Chart on page 4-5.
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ADJUSTMENTS (continued) Chart 1 1 1 1 1 1 1 1 Emergency Source Frequency Pickup Emergency Source Frequency Pickup (continued) 1234-5678 .. ncy Actuator- Poclflon" F,.. pIckup Fr.quency Actuator- Posltlonc pIckup "ettlng ... ttlng SwItch TrmL e ,. c e 90 p.rcenT 96 p 1234-...
SECTION 5 STANDARD FEATURES & OPTIONAL ACCESSORIES OPTIONAL MANUAL CONTROL REMOTE CONTROL These manual controls, if furnished, are connected and Feature 17. Terminal provisions for Area Protection re installed on the enclosure door, or is shipped loose for mote contact which opens to signal automatic transfer open-type automatic transfer switches.
OPTIONAL ACCESSORIES (continued) OPTIONAL PLANT EXERCISER Exercise Without Load without load for t h e Timer exer C ises the engine generator n ot ar D Ace. 1 1 C This timer, if furnished, is an additional plug set time period. The automatic transfer switch is in circuit board in the control panel.
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OPTIONAL ACCESSORIES (continued) Decide what day(s) you want to exer cise the engine-generator set. Read the following di rections completely before setting run days. Hold down the SET button and press both the TIME/ DAY and ON TIME buttons simultaneously; a is dis...
Signal light (red) indicates that the Emergency source is available. Replacement bulbs for standard application are: ASCO number 343978-3 green LED (Ace. 9C) Figure 5-1 3. Optional Accessories 9C and 9D. ASCO number 343978-1 red LED (Ace. 9D) For oil-tight, watertight, or weatherproof applications: ASCO number 397400-2 green LED (Ace.
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OPTIONAL ACCESSORIES (continued) OPTIONAL ACCESSORY ter the relay energizes. The TS coil is energized and the standard Sequence of Operation is resumed. MOTOR LOAD TRANSFER either source of power is not available when the inphase O Acc. 27, if furnished, is an inphase monitor control for monitor starts its sensing mode, the output relay picks up transfer and retransfer of motor loads, so that inrush cur...
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OPTIONAL ACCESSORIES (continued) $5 OR S6 OPTIONAL SELECTIVE LOAD 1 1. 1 1 1 1 . DISCONNECT CONTROL 1 2 3 4 5 6 7 8 These circuits, furnished, are supplied on an add-on panel and connected to the control panel. T wo sets of double-throw contacts are provided.
- '-'�-." . ".�- -�." ' " " .' .,� D I A G R A M lURE 9A & & FE;\. D C ! FEATUK'C:: 1 60 0 . 2000. 3000 4000 AMPS 1 000 1 200 AMPS 9ERGENCY a..
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P H Y S I C A L W I R I N G & 30 . 70 . 1 00 1 50 AMPS 400 AMPS SOO AMPS T�o LL I LOAD E>£RGENCY LOAD EMERGENCY LL I T6 0 LL I EL0 9 EMERGENCY 9 EL I...
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D I A G R A M FEATURE 1 600 . 2000 . 3000 , 4000 AMPS EMERGENCY 1 000 , 1 200 AMPS EMERGENCY EL I EL I I TS COlL, 9 0---' 1 1 I , · , 1 . 8 CKT I NORMAL 20 +- - - + - <>...
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MOST DOOR MOUNTED ACCESSOR I E S . REFER TO ASCO SUPPL I E D ACCESSORY NAMEPLATE DRAW I N G F O R 2 6 0 A N D 4 0 0 A M P T W O POLE S W I TCHES , FOR ACTUAL DOOR D R I LL I NG REOUIREMENTS .
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M I N I MUM BETWEEN L I VE METAL PARTS AND GROUNDED METAL . ASCO SUPPLIED ACCESSORY NAMEPLATE DRAWING FOR ACTUAL �OOR D R I L L I N G REO U I R E M E N T S WHEN OPEN TYPE ATS ' S ARE INTENDED FOR ENCLOSURE 5 .
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FLORHAM PARK . NEW JERSEY . 1 09279 1 60QACC2 OPEN TYPE 600 THROUGH 4000 AMPERE 07932 PR INTED IN U S A . AS�A ®940 1 0 9 1 1 9 HOLE C 6/89 1 0 7077 ISSUED 1 1 /88 PROPERTY OF AUTOMATIC SWITCH CO .
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DRIP SHIELD SUPPLIED ONLY ON FRONT AND SIDES. ---- -� TYPE 2 ENCLOSURES . 1 . 00 . 25 . 4 MM . OVERHANG TYPE ENCLOSURES FOR AUTOMAT IC TRANSFER S W I TCHES W I THOUT OPTIONAL ACC . OVERLAPPING NEUTRAL TRANSFER CONTACT F I G DIMENSIONS...
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TYPE 3R . 4 . 1 2 ENCLOSURES AUTOMATIC TRANSFER SWITCHES W I THOUT OPTIONAL 3 1 . 8 H MOUNTING TYP . ACC . 28 OVERLAPPING NEUTRAL TRANSFER CONTACT HOLE D I A D I MENSIONS SIZE 30 . 70 . 1 7 .
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ASCO automatic transfer switches, RC lighting contactors, engine and generator controls, SYNCHROPOWER® systems, and other ASCO electromagnetic/solid-state electronic controls. When you need that kind of assistance on any ASCO controls, contact the Authorized ASCO Service Center nearest you from the list below.
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C om bi nations of t h e above controls are also ava i l a b l e to meet i n d ividual :req u i rements. For i nformat i o n , contact y o u r nearest A S C O source or t h e ASCO Customer E n g i neeri n g Department_...
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