Eaton ATC-900 Operation And Maintenance Manual

Also see for ATC-900: Instruction booklet Manual Operation and maintenance manual Instruction booklet Operation and maintenance manual

Contents

For more information visit: www.eaton.com IB140064ENInstructional BookletPage 28 Effective: April 2018 Operation and Maintenance Manual, Automatic Transfer Switch, Bypass Isolation,Contactor Type, Open/Closed Transition, ATC-900 Controller, 3000A Frame8.2 Maintenance ProceduresA suggested maintenance procedure to follow is outlined inTable 4.Table 4. Periodic Maintenance Procedures.Figure 36. Contacts Behind ARC Chutes.Figure 37. Contacts.STEP ACTIONa. Make the transfer switch equipment safe for inspection and/or maintenance. Disconnect the line power from the equipment being serviced by opening next highest disconnect device. Makecertain that any accessory control power is switched off and the logic plugs are disconnected. Use proper Lock-out-Tagout procedures. The MIS switch could also be used to remove power from the components area on theslider door.b. Inspect the structure area for any safety hazards or potential maintenanceproblems.Inspect the area, especially where switching devices are installed, for any safety hazards, including personnelsafety and fire hazards. Exposure to certain chemical vapors can cause deterioration of electrical connections.Inspect for accumulated dirt, loose hardware, or physical damage.Examine the primary insulation for evidence of cracking or overheating. Overheating will show as discoloration,melting or blistering of conductor insulation, or as pitting or melting of conductor surfaces due to arcing.Inspect the secondary control connections for damage and the control wiring for insulation integrityc. Inspect the switching devices for dust, dirt, soot, grease, moisture, or corro-sion.Remove the dust, dirt, soot, grease, moisture, and corrosion contamination from the surface of the switchingdevice using a dry, soft lint-free cloth, dry, soft bristle brush, and vacuum cleaner. Do not blow debris into theswitching device or nearby the contactor structure. If contamination is found, look for the source and fix theproblem.d. Check for material integrity, uneven wear, discoloration, or loose hardware. Severe material cracking will require replacement and loose hardware will need to be tightened.e.Check all terminals and connectors for looseness or signs of overheating. Overheating will show as discoloration, melting, or blistering of conductor insulation.Connections that do not have signs of looseness or overheating should not be disturbed.f. Contact Inspection Procedure Loosen the arc chute retaining screws on the top rear of the contactor, then slide the molded cover toward theback of the contactor (Figures 36 & 37). The arc chute can then be lifted out of the molded case and the contactscan be inspected. Contact Eaton Care (1-877-ETN-CARE, Option-2, Option-4, Option-3) if the contacts haveexcessive wear. Reinstall the arc chute, slide the cover forward and tighten the retaining screw. For more infor-mation see section 7.4.1 on contact resistance.g. Exercise the switching devices if they are not often exercised while inoperation. This will permit a wiping action by the contacts.If a switching device is used for frequent switching during normal operation, this step can be disregarded. Thereare two automatic exercisers through the ATC-900 that are available to the user.h. Inspect NEMA 3R filters for blockage or contamination. For NEMA 3R enclosed transfer switches with venting, check that the air filters, if used are clean and uncompro-mised. Replace the filters as necessary.i. Return the transfer switch equipment to automatic service. Make certain that all barriers are in place and the doors are closed. Reapply the Source 1 and Source 2 power.Assure that the controller does not show "Monitor Mode" and the door lamps are not flashing.