[Richard]

If we go back to what changed, it takes us to the mysterious issue showing up just after the contractors were replaced. I would double check my wiring on the contractors cause if the neutral and hots were crossed up it could easily explain what you are seeing

[77newell]

One way to check the transfer switch would be to disconnect the wiring going to the main breaker box at the transfer switch, then try switching back and forth between Gen and plug-in supplies.

Before doing that I would check Gen voltage at the xfer switch.

Does anyone know what circuit is protected by the fuse that keeps blowing, what does that circuit do? I belive in some cases the fuse simply protects from shorts in the switch coils and in other cases it is blown to shut things down when a whole range of hazards are detected.

[NextNewell]

If we go back to what changed, it takes us to the mysterious issue showing up just after the contractors were replaced.  I would double check my wiring on the contractors cause if the neutral and hots were crossed up it could easily explain what you are seeing

Whatever the issue is now must be related to, or the result of, whatever caused the contractor to fail in the first place.

[HoosierDaddy]

If we go back to what changed, it takes us to the mysterious issue showing up just after the contractors were replaced.  I would double check my wiring on the contractors cause if the neutral and hots were crossed up it could easily explain what you are seeing

Whatever the issue is now must be related to, or the result of, whatever caused the contractor to fail in the first place.

Yes that is what I'm trying to understand. Did something fail causing the braided line to be a temporary conductor? Was that the initial "chatter" noise. If so the contacts could be replaced correctly but there's a problem somewhere else that is blowing the fuse. That is why I would advise caution if there is still some stray voltage that the braided line offered a temporary ground to.

[NextNewell]

If we go back to what changed, it takes us to the mysterious issue showing up just after the contractors were replaced.  I would double check my wiring on the contractors cause if the neutral and hots were crossed up it could easily explain what you are seeing

Whatever the issue is now must be related to, or the result of, whatever caused the contractor to fail in the first place.

Yes that is what I'm trying to understand. Did something fail causing the braided line to be a temporary conductor? Was that the initial "chatter" noise. If so the contacts could be replaced correctly but there's a problem somewhere else that is blowing the fuse. That is why I would advise caution if there is still some stray voltage that the braided line offered a temporary ground to.

I'm thinking it started with a faulty 50 to 30amp adapter that let the neutral become momentarly hot which started this domino effect?

[HoosierDaddy]

I would think a short in the adapter would blow breaker at the supply post. Were you connected to 30 amp supply? Can u check the adapter for continuity between those prongs?.. I was suspecting W/D because there is vibration/mechanical movement that could damage wiring etc. inside the machine. Have you been able to thoroughly inspect inside the W/D or check for continuity between the case and the plug prongs? The receptacle could be suspect except that there is little chance for movement that would precipitate damage.

[NextNewell]

So I still haven't resolved my electrical issue yet. I called Newell and after a lenghty conversation, he was stumped. Everything was wired correctly but he had no idea why it was blowing fuses. So I pulled out both contactors and double checked them for any visible issues, put copper selves on all incoming wires and separate connectors for the jumper wired ends. 

I have since started disconnecting the different sections of the coach in an attempt to see if I can isolate any issue. I started with just the store power connected to the box: fuse didn't blow. Next I connected the generator: fuse didn't blow. Then, before I connected the wires to power inside the coach on to the contactor, I disconnected the main wires to the breaker box inside just to see if the issue might be within that span: fuse didn't blow - BUT the red and black weren't hot at the breaker box either. I looked at the switch above the driver and it appeared fine. Ahhhhh!

[Richard]

Would you check your wiring to the contactor coils. The wiring on the contactors is obviously correct.

On your disconnecting wires strategy, when you disconnected at the breaker box, you said they were not hot. Do you get voltage at the transfer switch?

[77newell]

In the original picture of the box there are two fuse holders. Are both of them wired into the contactors? If so, I would guess they are each wired to a separate contactor coil. If so, I suggest turning odd all power and then measure the ohms resistance through each of the circuits to neutral or ground. They should be the same. The fuse blows due to too much current. Current will be too high if either the input voltage is too high or if the resistance in the coil is too low.

If the oil ohms are ideal tial then I would pull the power leads to the fuses loose and measure the input voltage. If those are also identical I'm gobsmacked stumped to explain the fuse blowing.

[jimg]

Have you unhooked the inverter? Some coaches were equipped with an inverter bypass plug. If not you will have to unhook the wires in the inverter for A/C input. Unplug the washer and dryer to eliminate it and anything else that can be unplugged. I suspect you had power going down the ground or neutral leg.