generator producing electric but not inside the cabin.

[Aquaman]

I have a older Rexhall Class A with a 5500 Generac generator. Brought to a Generac dealership and they it is producing the correct current but I have no power inside. They are not RV people so they had no answer. Before I take it to a RV shop I want to ask if anyone have any idea. I thinking the automatic transfer switch could be bad but I'm not even sure where that is on the vehicle. Any help would be appreciated.

 

[RKins]

To find your ATS follow the power cord into the power bay. If it has a cord reel, follow it out of that. If you have a surge protector follow the cord into and out of that and finally you'll find the ATS.

 

[Ernie Ekberg]

If you can plug in and get power, I bet it is the transfer switch. Mine went south last year.

 

[Chuggs]

Start at the Generator...usually a circuit breaker on it.

Secondly, the ATS (transfer switch). These employ two contactors. The shore side is a dumb contactor, it closes whenever L1 and Neutral have power from the shore cord UNLESS the Generator Contactor has closed. Generator takes priority and will kick off the shore power contactor. There is a mechanical linkage between the two to prevent the two sides from paralleling. The generator side of the ATS has a small circuitboard. It looks for stable power, and may have a delay built-in which can be overridden with a jumper. If that circuitboard isn’t happy..it won’t close the generator contactor. You can easily measure the voltage on the input and output side of the contactor. The PD52 is oriented with input from generator low left, shore power low right...and the outputs are jumped together high right to go to your coaches distribution panel. The lugs are supposed to be wired L1, Nuetral, L2. If you use a voltmeter in AC volts..testing the meter lug against the one to it’s left will measure the input. Doing the same on the top right contactor will show what’s getting thru to the coaches distribution panel.

Inside the coach...the wires from the transfer switch go in...on the dual 50A breaker labeled MAIN. If it is not tripped...you have power to the rails. Then each branch has circuit protection.

To recap...

Genset...built-in breaker

ATS...input and output of contactor. They usually aren’t very accessible...but if you have good input from the generator, but the generator contactor isn’t closing...you could have one of three different problems.

1) circuitboard isn’t powering the coil to close the generator contactor (faulty circuitboard)
2) contactor has failed...mechanically jammed or coil has shorted and won’t pull the armature closed.
3) Mechanical Interlock is jammed up. The interlock is mechanically holding the Generator contactor from closing because it is jammed. If the shore Contactor has opened...it should then allow the Generator contactor to close.

Main breaker in distribution panel.



If it is an emergency...NO shore power available, and you really really need the generator...you could remove the connector from the circuitboard and Jump the outer wires (Generator L1, and Generator Nuetral) to the inner two wires...which go to the contactor coil...orientation is inconsequential. If it was only a circuitboard issue...this should bypass that and close the contactor... and if the transfer switch still doesn’t work. Well...in that case you are replacing it anyway. Get some heat shrink and heavy duty rated joining lugs...take the transfer switch out. Directly connect the three input wires from the generator to the three output wires going to the distribution panel...making Sure to respect the polarity of the wires. L1 to L1, Nuetral to Neutral, L2 to L2. Leave the wires full length to allow reinstallation of a new transfer switch.

WARNING: Electricity is dangerous! Only perform these procedures if you are knowledgeable about how to make the system safe before handling the wiring to prevent accidental electrocution.

 

[Gizmo]

That happens every time my wife plugs in the hairdryer while we have to many other appliances running. It will either blow the breaker on the generator or the breaker on the inventor. Ether one we will have 12-volt power but no 120 AC power.

 

[Kevin D Pem]

You may not have a transfer switch. Look in the bay your cord is in and see if there is an outlet for the cord to plug into.