Cummins/Onan — Manual Operation
Operation · Transfer Switch
From a Cummins/Onan service manual covering: GT30160EQ5KA000, GT40063XN52A000, GT40063YN52A000, GT40063ZN52A000. Check it applies to your exact model before use.
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Before you start
- Manual operation of the transfer switch under load presents a shock hazard that can cause severe personal injury or death. Do not attempt to operate the switch manually when it is under load. Disconnect both sources of power before operating manually.
- If not removed, automatic transfer switch operation results in rapid movement of the manual operator handle and presents a hazard of severe personal injury. Remove the handle before switching back to automatic operation.
Procedure
- Verify that the transfer switch is not under load.
- Open the cabinet door of the automatic transfer switch.
- Remove power to the control by removing the FB fuse.
- To close Side A: place the handle on the transmission shaft and rotate it upwards until the switch locks.
- To open either side (Side A or Side B): remove the manual operation handle and press the trip with a screwdriver.
- To close Side B: place the handle on the transmission shaft, press and hold 'Select' with a screwdriver while rotating the handle upwards until the switch locks.
- Make sure the manual operation handle is removed from the transmission shaft and stored in a safe location.
- To return to automatic operation, restore power to the control by reinserting the FB fuse.
- Close the cabinet door.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Source: Cummins/Onan service manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.