Transfer switch?

[aunut]

Our last camping trip in our motorhome we smelled something like an electrical wire burning. We checked the interior to see wherein was coming from and I turned things on and off to check if they worked. Everything did work and the smell went away. I checked the bays and the strongest burnt smell seemed to be coming from the electrical bay where the power cord, installed surge protector and transfer switch are located. I touched the transfer switch box and it seemed to be pretty hot. I had never touched it before, so I don't know if it is supposed to be that warm to the touch. We left the next day, but before we left, we ran electrical appliances and there was no strong smell as before. The transfer switch was still warm to the touch. 

I've run the generator since returning with no hint of burning wire smell. Is there a test to see if the switch is bad?

[Wrknrvr]

 First thing is to see what make it is. Then how old is the coach. And what make a coach it is.

 

 Now the auto transfer switch is set to run on generator as the preferred power source. So when it does not detect generator power it then will switch to shore power. That is when there is shore power available.

 

 So what was happening with shore power is probably a loose connection or the points contact has a problem.

And no the unit should not be hot.

  This summer I had several transfer switch problems in my work as an RV tech. There is a new make of transfer switch on the market that I think has a manufacturing problem. Or that may be just my thoughts.

 

 It is made by Southwire. They were installed in newer Motorhomes.

 

 I had a new Southwire electric real for the power cord fail. Took it apart, it was poorly built inside. No parts available for it. Customer installed another make.

 

 

 Just me thinking again,.   Vern

[dennisvr]

If you are able, take off the cover of the transfer switch and check for burnt wires.  

[jblo]

Do all work with power off.....🙄

[aunut]

Thanks. It's in storage now and I'll open the box asap. By the way, it 's a Progressive Dynamics in a 2014 Winnie Vista.

[Kirk W]

6 hours ago, jblo said:

Do all work with power off..

The transfer device should be in good condition after 4 years of use, but if it has ever been abused you could have burned contacts or you could also have some loose wires. The generator should never be started with shore power connected and any large loads in operation. If starting the generator you need to turn off all major loads like air conditioners, microwave, electric heaters, and things of that nature or you can do major damage to the transfer contacts and also the things that you are operating. 

[Twotoes]

I alway unplug from shore power before starting my generator to avoid the hard switch back from gen to shore. Always with A/C off. I run the A/C while the gen is running to give it a load but turn it off before switching back to shore. My transfer switch went out on me last year. Found out that there was a loose wire that shorted it out. It was only 3 yrs old. Replaced it with a combo transfer and surge protector model so now I don’t have to plug in a surge protector at the pedestal. 

[aunut]

 I just went to the RV and removed the switch cover and saw that the red wire from the power cord coming in is black and burned about 2 inches up from where it is attached to the switch. The tightening screw also got hot and burned the yellow paint off it. All other wires and connections look to be in good condition.

All electrical items in the RV still work. Could this have been a faulty pedestal or do you think it's a damaged switch.

By the way, my surge protector is permanently in line AFTER the transfer switch.

[Darryl&Rita]

That damage is from a loose connection. Depending on whether the screw can be tightened, or not, will determine if the transfer switch is salvageable. Trim off the damaged wiring, and re-attach.

[aunut]

26 minutes ago, Darryl&Rita said:

That damage is from a loose connection. Depending on whether the screw can be tightened, or not, will determine if the transfer switch is salvageable. Trim off the damaged wiring, and re-attach.

Thanks. 

[Ray,IN]

3 hours ago, Darryl&Rita said:

That damage is from a loose connection. Depending on whether the screw can be tightened, or not, will determine if the transfer switch is salvageable. Trim off the damaged wiring, and re-attach.

Great advice! Many forget or fail to cut off the overheated copper wire, it has been annealed from the high heat, that makes it brittle.

[Kirk W]

6 hours ago, Darryl&Rita said:

That damage is from a loose connection. Depending on whether the screw can be tightened, or not, will determine if the transfer switch is salvageable. Trim off the damaged wiring, and re-attach.

It would not be a bad idea to also replace the screw just to be sure. I would also make sure that there contact area of the screw and wire are clean.

8 hours ago, aunut said:

Could this have been a faulty pedestal or do you think it's a damaged switch.

1

If that screw was loose it would easily account for the problem that you experience. The power pedestal would not cause that problem. 

[aunut]

2 hours ago, Kirk W said:

It would not be a bad idea to also replace the screw just to be sure. I would also make sure that there contact area of the screw and wire are clean.

If that screw was loose it would easily account for the problem that you experience. The power pedestal would not cause that problem. 

Thanks. I'm going to do just that. The guy at the manufacturer told me today that, because the cover was extremely warm to the touch that it was probably the switch. I don't buy that. If it was the switch, I don't think all electrical systems would have functioned.

[Kirk W]

8 hours ago, aunut said:

If it was the switch, I don't think all electrical systems would have functioned.

It is difficult to know exactly what the factory guy had in mind but if the contacts are badly burned that too could cause heat to be generated. No matter what the cause of the heat, there has to be current passing through and supplying the loads in the RV for heat to be generated and thus burn the wire and such. That could have been caused by burned contacts but a loose connection is more likely to have been the problem, particularly because you indicated the signs of being hot were all on the one lead and the screw. If you have a good light you should be able to see any signs of the contacts having been burned while you are there to repair the wire connection and replace the screw. I suggest that once you have it repaired, check the auto transfer switch (ATS) to be sure that it isn't getting hot. If you can't see any signs that the contracts are burned and it doesn't get hot while you are using lots of power then it is pretty safe to say that you have it repaired.