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Transfer Switch Sequence of Operations

After the "Timing for Start" timer times out, (this takes from 1 to 10 seconds) a signal is sent to the generator's engine to crank and the "Start Gen Set" light comes on.

When the engine starts, the generator begins to make A/C voltage.The "Source 2 Available light will come on when voltage becomes available from the generator. Also, when voltage becomes available from the generator the "Timing for Transfer" light will come on. This timer allows the engine to warm up. It prevents the contactor from switching the load to the generator for up to 120 seconds after the generator starts.

The generator A/C circuits are energized but the contactor is still connected to the now dead utility.

These lights should be on:

Start Gen Set
Source 2 Available
Transfer Timing