Operator’s Manual 7000 Series 7ADTB Automatic Delayed–Transition Transfer & Bypass–Isolation Switches H design 600 through 1200 amp. DANGER is used in this manual to warn of high voltages capable of causing shock, burns, or death. WARNING is used in this manual to warn of possible personal injury. Refer to the outline and wiring drawings provided with your 7000 Series ADTB for all installation and connection details and accessories. Refer to Group 5 Controller User’s Guide 381333–126 for ATS status display messages, time delays, pickup & dropout settings, and adjustments. An experienced licensed electrician must install the 7ADTB. CAUTION is used in this manual to warn of possible equipment damage. Rating Label Each 7000 Series 7ADTB contains a rating label to define the loads and fault circuit withstand/closing ratings. Refer to the label on the Transfer Switch for specific values. Do not exceed the values on the nameplate/ rating label. Exceeding the rating can cause personal injury or serious equipment damage. TABLE OF CONTENTS section-page INSTALLATION Mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 Power Connections . . . . . . . . . . . . . . . . . . . . 1-1 Engine Starting & Auxiliary Circuits . . . . . . 1-2 Functional Test . . . . . . . . . . . . . . . . . 1-2, 1-3, 1-4 TESTING & SERVICE Transfer Test . . . . . . . . . . . . . . . . . . . . . . . . . . Preventive Maintenance . . . . . . . . . . . . . . . . Disconnecting the Controller . . . . . . . . . . . . Manual Load Transfer . . . . . . . . . . . . . . . . . . Trouble-Shooting . . . . . . . . . . . . . . . . . . . . . . 2-1 2-1 2-1 2-2 2-2 BYPASSING & ISOLATING Bypassing the ATS . . . . . . . . . . . . . . . . . 3-1, 3-2 Isolating the ATS . . . . . . . . . . . . . . . . . . . 3-3, 3-4 Return to Service . . . . . . . . . . . . . . . 3-5, 3-6, 3-7 INDEX . . . . . . . . . . . . . . . . . . . . . . . . . back cover 600–1200 amp. sizes 50 Hanover Road, Florham Park, New Jersey 07932–1591 USA For sales or service call 1 800 800–2726 (ASCO) www.ascopower.com ASCO POWER TECHNOLOGIES CANADA PO Box 1238, 17 Airport Road, Brantford, Ontario, Canada N3T 5T3 telephone 519 758–8450, fax 519 758–0876, for service call 1 888 234–2726 (ASCO) www.asco.ca 381333–195 A Nameplate Catalog Number Identification The Transfer Switch nameplate includes data for each specific 7000 Series 7ADTB. Use the switch only within the limits shown on this nameplate. A typical Catalog Number is shown below with its elements explained. Typical 7000 Series 7ADTB catalog no. for switched neutral, 3 pole, 600 amp, 480 V, in Type 1 enclosure: H7ADTB Neutral A – solid B – switched blank – none Status Lights & Engine Control Bypass Handle B Phase Poles 2 – single Ø 3 – three Ø 3 600 Amperes 600 800 1000 1200 N 5 Voltage C 208 D 220 E 230 F 240 G 277 H 380 J 400 K 415 L 440 M 460 N 480 P 550 Q 575 R 600 C Controller 5 – standard 5X – if accessories ordered Enclosure C – type 1 F – type 3R G – type 4 L – type 12 blank – open type Transfer Control & Lights Group 5 Controller Isolation Handle Transfer Switch open–type H7ADTB with the lower door open (transfer switch shown) SECTION 1 INSTALLATION Testing Power Conductors ASCO 7000 Series Automatic Delayed–Transition Transfer & Bypass–Isolation Switches (7ADTBs) are factory wired and tested. Field installation requires mounting and connection of service cables, and auxiliary control circuits (if required). Do not connect the power conductors to the transfer switch until they are tested. Installing power cables in conduit, cable troughs and ceiling-suspended hangers often requires considerable force. The pulling of cables can damage insulation and stretch or break the conductor’s strands. For this reason, after the cables are pulled into position, and before they are connected, they should be tested to verify that they are not defective or have been damaged during installation. Remove the Shipping Skid Open the front door and remove the four lag screws (2 in front, 2 in rear) securing enclosure to the shipping skid. Protect the switch from construction grit and metal chips to prevent malfunction or shortened life of the 7ADTB switch. Supporting Foundation The supporting foundation for the enclosure must be level and straight. Refer to the applicable enclosure outline drawing included with the switch for all mounting details including door opening space. Connecting Power Conductors After the power cables have been tested, connect them to the appropriate terminal lugs on the bypass switch as shown on the wiring diagram provided with the switch. Make sure the lugs provided are suitable for use with the cables being installed. Standard terminal lugs are solderless screw type and will accept the wire sizes listed on the drawings provided with the 7ADTB. Be careful when stripping insulation from the cables; avoid nicking or ringing the conductor. Remove surface oxides from cables by cleaning with a wire brush. When aluminum cable is used, apply joint compound to conductors. Tighten cable lugs to the torque specified on rating label. If bottom cable entry is used, the foundation must be prepared so that the conduit stubs are located correctly. Refer to the enclosure outline drawing for specified area and location. Provide cable bending space and clearance to live metal parts. When a concrete floor is poured, use interlocking conduit spacer caps or a wood or metal template to maintain proper conduit alignment. Mounting Refer to the applicable enclosure outline drawing furnished with this switch and mount the automatic transfer switch according to details and instructions shown on diagram. Controller Ground A grounding wire must be connected to the controller’s lower left mounting stud. Because the controller is mounted on the enclosure door, a conductive strap must be used between the enclosure and the door. This connection provides proper grounding which does not rely upon the door hinges. Line Connections Refer to the Wiring Diagram provided with the switch. All wiring must be made in accordance with the National Electrical Code and local codes. Do not remove the interphase barriers from the transfer switch. Always protect the transfer switch, bypass switch, and isolation contacts and mechanisms from construction grit and metal chips when cabling. Harnesses The transfer switch is connected to the left side of the controller by a plug–in harness (two plugs). De–energize the conductors before making any line or auxiliary circuitry connections. Be sure that Normal and Emergency line connections are in proper phase rotation. Place engine generator starting control in the OFF position. Make sure engine generator is not in operation. 1---1 INSTALLATION (continued) Engine Starting Contacts All customer connections, including the engine control contact connections, are located on terminal block TB which is mounted on the top right side of the enclosure. Refer to the wiring diagram provided with the automatic transfer switch and connect the engine start wires to the appropriate terminals. See Figure 1–1 and Table A. Table A. Engine start connections. When normal source fails contact closes contact opens Terminals on Terminal Block TB TB1 and TB2 TB1 and TB3 engine start connections on customer terminal block TB Note: To temporarily disable engine control from the automatic transfer switch you can unplug J3 from the small P3 receptacle at the bottom of the assembly. Be sure to reconnect plug J3 to the P3 receptacle for automatic transfer switch operation. Auxiliary Circuits Connect auxiliary circuit wires to appropriate terminals on transfer switch terminal block TB as shown on the wiring diagram provided with this automatic transfer switch. Figure 1-1. Customer terminal block on the top right side of the enclosure. Functional Test Read all instructions on the Wiring Diagram and labels affixed to the automatic transfer & bypass–isolation switch. Note the control features that are provided and review their operation before proceeding. The Functional Test consists of two checks: ❐ 1 — Voltage Checks, page 1–3 ❐ 2 — Electrical Operation, page 1–4 Continue to 1 – Voltage Checks on next page. Do these checks in the order presented to avoid damaging the 7ADTB. 1---2 INSTALLATION (continued) GREEN RED GREEN RED observe these lights AMBER Figure 1-2. Standard controls and indicators. Close the normal source circuit breaker. The Transfer Switch 1 Connected To Normal and the Normal Source Accepted lights should come on. Functional Test Read all instructions on the Wiring Diagrams and labels affixed to the 7ADTB. Note the control features that are provided and review their operation before proceeding. Load Disconnect Active Use an accurate voltmeter to check phase to phase and 2 phase to neutral voltages present at the transfer switch normal source terminals. After installing the 7ADTB check the following: – Bypass Handle should be in the NORMAL position. – Isolation Handle should be in the CONN position. – CN transfer switch should be C (closed) – CE transfer switch should be O (open) Close the emergency source circuit breaker. (Start generator, if necessary.) The Transfer 3 Switch Connected To Normal & Emergency Source Accepted lights should come on. If handles are not in correct positions, follow instructions for Bypassing and Isolating the automatic transfer switch in Section 3. Do not force the handles. Electrical interlocks prevent a wrong sequence of operation. Load Disconnect Active Use an accurate voltmeter to check phase to phase and 4 phase to neutral voltages present at the transfer switch emergency source terminals.* 1 – Voltage Checks First check nameplate on transfer switch; rated voltage must be the same as normal and emergency line voltages. Use a phase rotation meter to check phase rotation of emer5 gency source; it must be the same as the normal source. Use extreme caution when using a meter to measure voltages. Do not touch power terminals; shock, burns, or death could result ! Perform steps 1–6 at the right. Observe the status lights. See Figure 1–2. ■ Black square means light is on. ❐ White square means light is off. Shut down the engine–generator, if applicable. The Emergency Source Accepted light should 6 go off. Then put the starting control selector switch (on the generator set) in the automatic position. Close enclosure door. * If necessary, adjust voltage regulator on generator per the manufacturer’s recommendations. The 7ADTB will respond only to rated voltage specified on the nameplate. Now continue to 2 – Electrical Operation on next page. 1---3 A B C Load Disconnect Active INSTALLATION (continued) GREEN RED GREEN RED operate this switch observe these lights AMBER Figure 1-3. Standard controls and indicators. Turn and hold Transfer Control switch clockwise to Transfer Test until the engine starts 1 and runs (within 15 sec.). The Emergency Source Accepted light should come on. 2 – Electrical Operation This procedure checks electrical operation of the ADTS. Close enclosure door before proceeding to prevent personal injury in case of electrical system fault. Transfer switch CN opens and the Transfer Switch Connected to Normal light should go off 2 and the Load Disconnect Active light should come on. Both CN & CE contacts are now open. Transfer Test The ATS should still be bypassed. Both normal and emergency sources must be available and the emergency source generator (if used) must be capable of being started; put engine starting control in automatic position. The Transfer Switch Connected to Normal light and the Normal Source Accepted light should be on. 1. After the delay transition time delay, the CE Transfer switch will operate to the Emergency 3 position. The Transfer Switch Connected To Emergency light should come on and Load Disconnect Active light goes off. Transfer switch will operate back to Normal position after Feature 3A time delay. For immediate retransfer turn Transfer Control counterclockwise to 4 Retransfer Delay Bypass. The Transfer Switch Connected To Normal light should come on; Transfer Switch Connected to Emergency light should go off. Turn the Isolation Handle counterclockwise to the TEST position. NOTE: The engine generator may be signalled to start while turning the Isolation Handle. If emergency source is available, the ATS may operate to the emergency position. If it does, operate Retransfer Delay Bypass switch. 2. Perform steps 1–5 at right. Observe the status lights. See Figure 1–3. ■ Black square means light is on. ❐ White square means light is off. 3. Turn the Isolation Handle clockwise to the CONN (connected) position. 4. Turn Bypass Handle clockwise to the OPEN position. The engine–generator will stop after the Feature 2E time delay 5 (unloaded running engine cooldown). The Emergency Source Accepted light should go off. This completes the Functional Test of the 7ADTB. 1---4 Load Disconnect Active Load Disconnect Active Load Disconnect Active Load Disconnect Active Load Disconnect Active SECTION 2 TESTING & SERVICE TRANSFER TEST REPLACEMENT PARTS Test the Automatic Transfer Switch portion of the 7000 Series 7ADTB at least once a month. This procedure checks the electrical operation of the Transfer Switch and Controller. Put the engine–generator starting control (at the engine–generator set) in automatic mode. Replacement parts are available in kit form. When ordering parts provide the Serial No., Bill of Material No. (BOM), and Catalog No. from the transfer switch nameplate. Contact your local ASCO Power Technologies Sales Office or ASI: In the following test the generator will start, the load will be transferred to the Emergency source, then back to the Normal source. An interruption to the load will occur, unless the the Transfer Switch contacts are bypassed before the test. See pages 3–1 through 3–4 for bypassing & isolating instructions if no interruption of load is required. In the United States call 1 – 800 – 800 – ASCO ( 2726 ) In Canada call 1 – 888 – 234 – ASCO ( 2726 ) DISCONNECTING THE CONTROLLER The harness disconnect plugs are furnished for repair purposes only and should not have to be unplugged. If the controller must be isolated, follow these steps: Be sure to close the enclosure door before proceeding to prevent personal injury in case of electrical system fault. Perform the five–step Electrical Operation – Transfer Test procedure on page 1–4. PREVENTIVE MAINTENANCE Reasonable care in preventive maintenance will insure high reliability and long life for the 7000 Series 7ADTB. An annual preventive maintenance program is recommended. Bypass–Isolation Switch is energized! Do not touch isolation contact fingers; shock, burns, or death could result! Disconnecting the Plugs 1. Bypass and Isolate the Automatic Transfer Switch. 2. Open the upper enclosure door. 3. Separate the two quick disconnect plugs by squeezing the latches. Do not pull on the harness wires. ASCO Services, Inc. (ASI) is ASCO Power Technologies’s national service organization. In the US ASI can be contacted at 1-800-800-2726 for information on preventive maintenance agreements. Reconnecting the Plugs 1. The ATS should be still bypassed and isolated. Checklist for Yearly Inspection 2. The two harness plugs and sockets are keyed. Carefully align the plugs with the sockets and press straight in until the latches click. Hazardous voltage capable of causing shock, burns, or death is used in this switch. Deenergize both Normal – Emergency power sources before performing inspections! 3. Close the enclosure doors. 4. Follow Return to Service instructions on page 3–5. ❐ Clean the 7ADTB enclosure. Brush and vacuum away any excessive dust accumulation. Remove any moisture with a clean cloth. ❐ Check the transfer switch contacts. Bypass, isolate, and withdraw the transfer switch. Then remove the transfer switch interphase barriers and check the condition of the contacts. Replace contacts when pitted or worn excessively. Reinstall the interphase barriers carefully. See page 3–4. ❐ Maintain transfer switch lubrication. If switch is subjected to severe dust or abnormal operating conditions, renew factory lubrication on all movements and linkages. Relubricate solenoid operator if TS coil is replaced. Don’t use oil; order lubrication kit 75-100. ❐ Check all cable connections & retighten them. 2---1 MANUAL LOAD TRANSFER This procedure manually transfers load to other source if the Transfer Switch or Controller are out of service. Close enclosure doors to prevent personal injury in case of electrical system fault. 1. Bypass the connected 7ADTB source. Turn Bypass Handle to EMERGENCY or NORMAL (see page 3–2). 2. Isolate to Test. Turn the Isolation Handle to TEST position (see page 3–3). 3. Turn the Bypass Handle to OPEN, then to the other source (see page 3–1). The load will be interrupted. 4. Turn the Isolation Handle clockwise to the CONN [connected] position (see page 3–4). TESTING & SERVICE (continued) TROUBLE-SHOOTING Note any optional accessories that may be furnished on the 7ADTB and review their operation. Refer to any separate drawings and/or instructions that may be packed with the 7ADTB. See Table B. Hazardous voltage capable of causing shock, burns, or death is used in this switch. Do not touch the power or load terminals of the bypass switch or transfer switch! Table B. Trouble-Shooting Checks. PROBLEM Engine–generator set does not start when the Transfer Control switch is turned and held in Transfer Test position or when normal source fails. CHECK IN NUMERICAL SEQUENCE 1 OPERATION 2 GEN-SET Hold Transfer Test switch 15 Starting control must be in the seconds or the outage must automatic position. Batteries be long enough to allow for must be charged and Feature 1C time delay plus connected. Check wiring to engine cranking and starting. engine starting contacts. 3 VOLTAGE --- Transfer switch does not transfer the load to the emergency source after the engine–generator set starts. Wait for Feature 2B time delay Generator output circuit breaker must be closed. to time out. Generator frequency must be at least 95% of nominal (57 Hz for a 60 Hz system.) * Voltmeter should read at least 90% of nominal phase to phase voltage between terminals EA and EC (or EL1 and EL2 for 2 pole switches)* Transfer switch does not transfer the load to normal source when normal returns or when the Transfer Control switch is released. Wait for Feature 3A time delay to time out. Voltmeter should read at least 90% of nominal phase to phase voltage between terminals NB and NC, NC and NA, and NA and NB (or NL1 and NL2 for 2 pole switches). Gen. does not stop after load retransfer to normal source. Load Disconnect Active light comes on. Load Disconnect Active light stays on longer than 6 min. Wait for Feature 2E time delay to time out. Wait for load disconnect time delay to time out. Check load disconnect time delay setting. Call ASI. --- Starting control must be in the --automatic position. Explanation: Transfer switch in delayed transition transfer mode. Load disconnect time delay is adjustable from 0 to 5 min. 59 sec. Explanation: Transfer switch contacts are open longer than 5 min. 59 sec (maximum setting). Load remains disconnected. * These are factory settings. Refer to Controller’s User’s Guide. If the problem is isolated to circuits on the controller or the transfer switch, call your local ASCO Power Technologies sales office or ASI: in the United States, call 1–800–800–2726 or in Canada call 1–888–234–2726. Furnish the Serial No., Catalog No., and Bill of Material (BOM) No. from the transfer switch nameplate. MAINTENANCE HANDLE Emergency contacts (upper shaft) Bypass and isolate the Transfer Switch before using the maintenance handle! See pages 3–1 through 3–4. Remove the maintenance handle after using it; store it inside. 1. 2. Bypass, isolate, and withdraw the transfer switch (pages 3–1 through 3–4). Then locate and remove the maintenance handle from the clip (inside lower left side). Insert the handle onto the shaft on the left side of the operator of the transfer switch See Figures 2–1, 2–2, 2–3 and Table C. Move the maintenance handle up or down as shown to manually operate the transfer switch. Operate both upper and lower contact shafts. Observe the window indicators (right side). Remove the maintenance handle and store it on the lower left side. 2---2 window indicators O is open C is closed contact position indicators (right side) Normal contacts (lower shaft) Figure 2–1. Contact position indicators. Note: If Normal and Emergency connections are reversed this operation is also reversed. TESTING & SERVICE (continued) handle UP opens the Emergency source contacts frame UPPER SHAFT DOWN closes the Emergency source contacts shaft Figure 2–2. Maintenance handle operation for Emergency source contacts (upper shaft). handle UP closes the Normal source contacts frame LOWER SHAFT DOWN opens the Normal source contacts shaft Figure 2–3. Maintenance handle operation for Normal source contacts (lower shaft). Transfer Switch Position Table C. Maintenance handle positions. Interlocked Weights Lobes prevent closing Maintenance Handle both N & E contacts up weight shaft E=O E upper contacts open lobe Normal Shaft Indicators lobe N up shaft N=C lower contacts closed weight up Load Disconnected E=O E upper contacts open N=O N lower contacts open down E=C E down Emergency upper contacts closed N=O N lower contacts open down 2---3 SECTION 3 BYPASSING & ISOLATING BYPASSING THE ATS* This procedure explains how to Bypass the closed transfer switch contacts. Bypassing is required before the Transfer Switch can be tested or isolated. The Bypass Switch Handle must be in the OPEN position (green window indicator) and the Isolation Handle must be in the CONN [connected] position (window indicator). The TS Connected light must be on. See Figures 3–1, 3–2, 3–3. You can only bypass to the same source that the Transfer Switch is connected. Solenoid interlock prevents incorrect operation. 1. Observe which Transfer Switch Connected To light is on (Normal or Emergency) on the door. This is the position of the transfer switch (see Figure 3–2). 2. Follow the directions on next page to Bypass to the same source as connected to transfer switch (select Normal or Emergency). Window indicator shows yellow when ATS is bypassed to Emergency. Window indicator shows green when the ATS is not bypassed. Figure 3–1. Status lights and Engine Control. Upper green light is on if Transfer Switch is on Normal. Lower red light is on if Transfer Switch is on Emergency. TRANSFER SWITCH Window indicator shows yellow when ATS is bypassed to Normal. CONNECTED TO NORMAL Figure 3–4. Bypass Handle and three position window indicators. CONNECTED TO EMERGENCY Figure 3–2. Status lights for Transfer Switch main contact position. Upper amber light should be on. Allowable Positons of the Bypass Switch in relation to Positons of the Transfer Switch (with Isolation Handle in the Conn [connected] positon and TS Connected light on) TS CONNECTED Transfer Switch TS TEST If Transfer Switch is in Normal position. If Transfer Switch is in Emergency position. TS ISOLATED Figure 3–3. Status lights for Transfer Switch isolation contact position. 3---1 Bypass Switch can be in either Open or Normal Open or Emergency BYPASSING & ISOLATING To Bypass Normal Source* (Load connected to Normal Source) The Transfer Switch Connected To Normal light is on and Transfer Switch Connected To Emergency light is off. (Load connected to Emergency Source) The Transfer Switch Connected To Emergency light is on and Transfer Switch Connected To Normal light is off. Push in the handle and turn it counterclockwise.* Turn the handle clockwise.* Push in* the Bypass Handle all the way, then turn it counterclockwise until Bypass Switch Position shows closed on NORMAL (yellow window indicator). The green light Bypassed to Normal will come on and the amber light Not In Automatic will flash. Push in Bypass Handle and turn it counterclockwise. (continued) To Bypass Emergency Source* Bypass Switch Turn* the Bypass Handle clockwise until Bypass Switch Position shows closed on EMERGENCY (yellow window indicator). The red light Bypassed to Emergency will come on and the amber light Not In Automatic will flash. E Bypass Switch Turn Bypass Handle clockwise. L L N N ATS ATS Figure 3–5. Bypass to Normal diagram. Upper green light comes on E Figure 3–7. Bypass to Emergency diagram. BYPASS SWITCH BYPASS SWITCH BYPASSED TO NORMAL BYPASSED TO NORMAL Lower red light comes on BYPASSED TO EMERGENCY BYPASSED TO EMERGENCY Upper window indicator EMERGENCY shows yellow Lower window indicator NORMAL shows yellow Figure 3–6. Status light and window indicator for Figure 3–8. Status light and window indicator for Bypassed to Normal Source. Bypassed to Emergency Source. The automatic transfer switch can now be put in the TEST or OPEN position. See ISOLATING on page 3–3. * NOTE: When Accessory 40*B (reversed Normal & Emergency connections) is specified, the handle operation is reversed. Follow instructions on the door. 3---2 BYPASSING & ISOLATING ISOLATING THE ATS Isolating is required before any service work can be performed on the automatic transfer switch (ATS). Refer to Figures 3–9, 3–10, 3–11, and 3–12. Hazardous voltage capable of causing electrical shock, burns, or death; do not touch any control circuit terminals. 1. Bypass the closed automatic transfer switch contacts. See BYPASSING on pages 3–1 and 3–2. 2. Turn the Isolation Handle counterclockwise (approx. 8 turns) until window shows TEST. The TS Test amber light should come on. The ATS can be tested now without load interruption (see page 2–1). Bypass Switch Turn crank counterclockwise until window shows TEST. (continued) NOTE: In the TEST position the transfer switch solenoid operator circuit is energized through secondary disconnects. 3. Continue turning Isolation Handle counterclockwise (approx. 6 turns) until the window shows ISOLATE. The TS Isolated amber light should come on. Bypass Switch E Turn crank counterclockwise until window shows ISOLATE. L L N N Automatic Transfer Switch Automatic Transfer Switch Figure 3–11. TEST to ISOLATE position. Figure 3–9. CONNECTED to TEST position. Middle amber light should be on. E TS CONNECTED TS CONNECTED TS TEST TS TEST Lower amber light should be on. TS ISOLATED TS ISOLATED CONN counterclockwise – draws TEST out the transfer switch ISOLATE Figure 3–12. Isolation Handle turned to ISOLATE. CONN counterclockwise – draws TEST out the transfer switch ISOLATE Figure 3–10. Isolation Handle turned to TEST. position window position window 3---3 BYPASSING & ISOLATING 4. Open the lower enclosure door. Pull out both left and right side rails then use the two handles to roll out the transfer switch. It can be safely inspected in this position. The transfer switch can also be removed for easier maintenance operations. See Figure 3–13. (continued) To prevent the possibility of fatal electrical shocks and burns, bypass, isolate, and withdraw the transfer switch before working on it. The contact assemblies (two for each pole) are located to the right of the operator mechanism. Hazardous voltage capable of causing electrical shock, burns, or death; do not touch any control circuit terminals. 1. Deenergize transfer switch (pages 3–1 thru 3–4) Bypass, isolate, and withdraw transfer switch. Use a voltmeter to verify that no electrical power is present at the transfer switch terminals. 2. Use the maintenance handle (page 2–2). Open the contacts that will be inspected by using the detachable maintenance handle. 3. Remove the interphase barriers (Figure 3–14). Use a blade screwdriver to loosen (ccw) four round–head screws holding each barrier to the arc chutes. Slide barrier up until keyholes clear the round–head screws, then remove it. handles arc chutes left rail loosen (ccw) round–head screws (do not remove) right rail Figure 3–13.Transfer switch isolated and pulled out for inspection. See page 2–2 for maintenance handle use. A lifting yoke 734408 is available to facilitate lifting by using an overhead crane or similar equipment. See WARNING. keyslots The Transfer Switch weighs 165–235 lbs. depending upon the number of poles. Use lifting device 734408 or other device capable of lifting this weight to avoid personal injury or equipment damage. Two persons are recommended. interphase barrier loosen (ccw) round–head screws (no not remove) Contact Inspection The main contacts are protected by arcing contacts. The arcing contacts make first and break last to avoid arcing at the main contacts. Contact condition should be checked annually. Contacts should be replaced when contact material becomes severely worn. Discoloration is normal. Do not file contacts because it wastes material. Instead use light emery paper to clean up the contact surfaces. keyslots insulator nuts Figure 3–14. Interphase barrier removal. 4. Remove the arc chutes. Use a 5/8” nutdriver to remove (ccw) two long insulator nuts. Then pull the arc chute outward (off the long threaded rods). See Figure 3–14. If the contacts need to be replaced see page 2–2. 3---4 BYPASSING & ISOLATING 5. Remove the movable contact cover. Use your thumb and fingers to squeeze the sides inward until the contact cover is released from the shaft clamp (both sides). Then remove the movable contact cover. See Figures 3–15 & 3–16. (continued) RETURN TO SERVICE This procedure explains how to return the automatic transfer switch (ATS) to service after inspection and maintenance. Observe the Bypass Switch Position indicator and lights). 1. Use the two handles to roll the transfer switch into the enclosure (isolation contacts facing inward) until its crank pins engage the latch plates on both sides. Next push in both side rails and close enclosure door. s queeze movable contact cover to releas e it handles Figure 3–15. Movable contact cover release. shaft clamp right rail left rail movable contact cover Figure 3–17.Transfer switch isolated and pulled out for inspection. Figure 3–16. Movable contact cover removal. Close the enclosure door to prevent personal injury in case of electrical system fault. 2. Turn Isolation Handle clockwise (approx. 6 turns) until the window shows TEST and TS TEST light comes on. 6. Reinstall the movable contact cover. After inspection reinstall the movable contact cover onto the movable contact assembly. Use your thumb and fingers to squeeze the sides inward until the contact cover is latched onto the metal bracket (both sides). Figures 3–15 & 3–16. Bypass Switch E Turn crank clockwise until window shows TEST. 7. Reinstall the arc chute. Slide the arc chute (arc splitters toward the contacts and recess for nuts outward) between the two long threaded rods. Reinstall the two long insulator nuts (round shoulder in) and use a 5/8” nutdriver to GENTLY tighten (cw) until snug. Do not overtighten these nuts. See Figure 3–14. L N 8. Reinstall the interphase barrier. Install the barrier over the arc chutes and slide it up until the four round–head screws align in the four keyholes in the barrier. Then slide the barrier down. Use a blade screwdriver to tighten (cw) the four round–head screws to secure the barrier to the arc chute insulator nuts. See Figure 3–14. Automatic Transfer Switch Figure 3–18. ISOLATE to TEST position. 3---5 BYPASSING & ISOLATING Do not close the isolation contacts unless the Transfer Switch (ATS) and Bypass Switch are in the same position! TS CONNECTED Middle amber light should come on. (continued) TS TEST TS ISOLATED 6. When the transfer switch is in the same position as the Bypass Switch handle, continue turning the Isolation Handle clockwise (about 8 turns) until the window shows CONN (connected). Bypass Switch Turn crank clockwise until window shows TEST. position window TEST E L clockwise – draws in the transfer switch N Figure 3–19. Isolation Handle turned to TEST. 3. The ATS can be tested now without load interruption (see page 2–1). Automatic Transfer Switch Figure 3–20. TEST to CONN (connected) position. Upper amber light should be on. Solenoid interlock prevents you from closing the isolation contacts until the ATS is in the same position as the Bypass Switch. TS CONNECTED TS TEST 4. Observe which Bypass Switch Position window indicator is yellow (NORMAL or EMERGENCY) at the Bypass Switch Handle. This indicates the source connected to the load. 5. Observe which Transfer Switch Connected To light is on (Normal or Emergency) on the door. This is the position of the Transfer Switch. If it is not in the same position as the Bypass Handle change the position of the Transfer Switch as follows: TS ISOLATED To change the position of transfer switch Operate to NORMAL Turn Transfer Control switch to Retransfer Delay Bypass. Connected To Normal light should come on. Operate to EMERGENCY Turn Transfer Control switch to Transfer Test (hold 15 seconds).* Connected To Emergency light should comes on. CONN position window * If Feature 2B time delay is used, there will be a delay before transfer to Emergency. CONN clockwise – draws in the transfer switch Figure 3–21. Isolation Handle turned to CONN. NOTE: With Normal available, the automatic transfer switch will not stay in the emergency position unless Feature 3A time delay is used (at least 30 seconds). 3---6 BYPASSING & ISOLATING RETURN TO SERVICE continued* (continued) Indicator shows yellow when ATS is bypassed to Emergency. This procedure explains how to return the Bypass Switch Handle to the OPEN position. The Bypass Handle must be in the CLOSED position (yellow indicator on NORMAL or EMERGENCY) and the Isolation Handle must be in the CONN position (window). See Figures 3–22, 3–23, and 3–24. Indicator shows green when the ATS is not bypassed. You can only bypass to the same source that the ATS is connected. Solenoid interlock prevents incorrect operation. 1 2 Observe which Bypass Switch Position indicator is yellow (NORMAL or EMERGENCY) at the Bypass Switch Handle. This indicates the source connected to the load. Un–Bypass to same source as the Bypass Switch Position as follows (select Normal or Emergency). Indicator shows yellow when ATS is bypassed to Normal. Figure 3–22. Bypass Handle and position indicators. To Un–Bypass Normal Source* To Un–Bypass Emergency Source* (Load connected to Normal Source) The Transfer Switch Connected To Normal light is on and Transfer Switch Connected To Emergency light is off. (Load connected to Emergency Source) The Transfer Switch Connected To Emergency light is on and Transfer Switch Connected To Normal light is off. Turn the handle clockwise.* Turn the handle counterclockwise.* Turn* the Bypass Handle clockwise until the Bypass Switch Position shows OPEN (green window indicator). The Bypassed to Normal light should go off and the Not In Automatic light should go off. Turn Bypass Handle clockwise. Bypass Switch Turn* the Bypass Handle counterclockwise until the Bypass Switch Position shows OPEN (green window indicator). The Bypassed to Emergency light should go off and the Not In Automatic light should go off. E Turn Bypass Handle counterclockwise. L Bypass Switch E L N N ATS ATS Figure 3–23. Un–Bypass Normal diagram. Figure 3–24. Un–Bypass Emergency diagram. The Automatic Closed–Transition Transfer & Bypass–Isolation Switch should be left in this position. * NOTE: When Accessory 40*B (reversed Normal & Emergency connections) is specified, the handle push–pull operation is reversed. Follow instructions on the door. 3---7 INDEX A auxiliary circuits, 1–2 B I indicators, contact position, 2–2, 2–3 inspection, 3–1 installation, 1–1 barriers, interphase, 3–4, 3–5 interlocked weights, 2–3 bypassing the ATS, 3–1, 3–2 interphase barriers, 3–4, 3–5 isolating the ATS, 3–3, 3–4 C L catalog number, 1–1 lifting device, transfer switch, 3–4 cleaning, 2–1 lights, 1–2, 1–3, 3–1, 3–2, 3–3 connections power, 1–1 load connected to emergency, 1–3 contact inspection, 3–4, 3–5 controller disconnecting, 2–1 see Controller User’s Guide D delayed transition transfer, 1–4 see Controller User’s Guide E electrical operation, 1–4 Emergency Source Accepted light, 1–3 engine starting contacts, 1–2 F foundation, 1–1 frequency, generator, 2–2 functional test, 1–2, 1–3, 1–4 H R rating label, cover replacement parts, 2–1 return to service, 3–5, 3–6, 3–7 S service ASCO Services, Inc. (ASI), 2–1 settings see Controller User’s Guide load connected to normal, 1–3 Load Disconnect Active light, 1–4 lubrication, 2–1 M maintenance, preventive, 2–1 T test, functional, 1–2, 1–3, 1–4 testing power cables, 1–1 maintenance handle, 2–3 warning, 2–3 time delays, 2–1 see Controller User’s Guide manual load transfer, 2–3 warning, 2–3 Transfer Control selector switch Retransfer Delay Bypass, 1–3 Transfer Test, 1–3 N nameplate, 1–1 Normal Source Accepted light, 1–3 O operation electrical, 1–4 manual, 2–3 warning, 2–3 optional accessories see Controller User’s Guide P Transfer Switch Connected To Emergency light, 1–3 Transfer Switch Connected To Normal light, 1–3 transfer test, 1–4, 2–1 transfer to emergency, 1–4, 2–1 transfer to normal, 1–4, 2–1 troubleshooting, 2–2 V harness, 1–2 disconnect plugs, 2–1 parts, 2–1 HELP firstname.lastname@example.org 800–800–2726 (ASCO) phase rotation check, 1–3 voltage checks, 1–3 preventive maintenance, 2–1 voltage, pickup and dropout settings see Controller User’s Guide Printed in U.S.A. problem, 2–2 Copyright 2007 ASCO Power Technologies, L.P.