1999 American Coach Electrical Problem

[LJoyE53@aol.com]

Everything works properly on generator side of power. On shore power, front air and microwave will not run. Source manager (inverter) has been checked out to be fine. Anyone have any ideas as to what's happening? Never had a problem like this before.

Thanks!

[wolfe10]

This ASSUMES you have a voltmeter and are safe working with 120 VAC.

Start by verifying that you indeed have the proper 120 VAC. If on 50 amp, check CG outlet from each outer straight to inner straight and then inner round. Readings whould be 120 VAC. From one outer stright to the other, reading should be 240 VAC. And from center straight to center round zero.

If the CG outlet is OK, check at the coach-end of shore power cord. If OK, next place to check is at the ATS (Automatic Transfer Switch).

If only inverter powered circuits are not working, check for power in to the inverter. Many inverters have a pass through feature with a small fuse inside the inverter case.

Brett Wolfe

[gbrinck]

Everything works properly on generator side of power. On shore power, front air and microwave will not run. Source manager (inverter) has been checked out to be fine. Anyone have any ideas as to what's happening? Never had a problem like this before.

Thanks!

Odds are you have no power on 1/2 the 120vac load center (breaker box) when on shore power. 50A shore power consists of two 120V feeder circuits, both of which pass through the Source Manager's transfer switch and each one feeds half the circuit breakers. If one of the two "legs" of power is missing, you get your symptoms. The points of failure are the shore power itself (no power on one leg of the outlet), a bad pin or wire on your shore power cord, or a failing transfer switch (one of the two legs is stuck in the generator position). The breaker box itself is ok, since it works correctly in generator mode.

Brett Wolfe already explained how to isolate where the failure is.