problems with transfer switch, I think.

[klentzwh1]

I have a 2000 Winnebago Journey 34B, with an Onan diesel generator.
when I first start the generator, it runs normal for about 30 seconds, then slows to idle. the transfer switch never transfers to the generator mode. Any suggestions?

[gerdutch]

You check the breaker switch on the grrneratot?

[ADA]

The transfer switch may have failed or it is possible the 50 amp wiring on the terminal strip inside the switch may have loosened due to the jarring and shocks from being on the road. This is easy to check.

Turn off the generator and disconnect the power cord. You don't want any voltages present as you work inside the box. Remove the transfer switch cover and note there are three sets of wires coming into the box and fastened to a terminal strip. Tighten the connections on both sides of the strip. If any were loose it is possible that is the problem.

The relays in the transfer switch have contacts that can wear over time from the high currents, and you may have to replace the box.

Good luck

[keger]

While your generator is running check your line voltage it may be too high or too low causing the generator to shut down.

[marjoa]

Originally Posted by ADA

The transfer switch may have failed or it is possible the 50 amp wiring on the terminal strip inside the switch may have loosened due to the jarring and shocks from being on the road. This is easy to check.

Turn off the generator and disconnect the power cord. You don't want any voltages present as you work inside the box. Remove the transfer switch cover and note there are three sets of wires coming into the box and fastened to a terminal strip. Tighten the connections on both sides of the strip. If any were loose it is possible that is the problem.

The relays in the transfer switch have contacts that can wear over time from the high currents, and you may have to replace the box.

Good luck

Yep...very good possibility. JIC, here's a pic of what he's saying to check.

[snowman1]

Just had the exact same problem about 2 months ago. Went to exercise the Onan 7.5 QD one weekend and had no 120 volt power from the genny into the coach. The Onan generator was doing exactly what yours is doing which was odd, it never idled that low before. Turned off the genny, plugged back into shore power and had 120 volt power into the coach. Unplugged the coach, fired up the genny and pulled off the electrical access panel on the right front of the genny. Had 120 volts there so that pretty much ruled out the genny, thank goodness. That can get real spendy in a hurry. Was pretty sure it was the ATS.

Had my mobile RV mechanic come in and make the final diagnosis and do the repair. It was the old Todd Engineering PS-250 transfer switch finally giving up. He replaced the Todd switch with a Progressive Dynamics ATS. Was an exact replacement which is a big plus unless you like re-routing huge cables and using bad words. 2 hours labor and $180 bucks for the transfer box and all was well.