Overheated shore power wiring to transfer switch

[mfsmith57]

Hi Members, I recently purchased a 2014 Redwood 36RL, and I have the 5.5K Onan generator. During my first camping trip, I had an issue with the transfer switch, where it would not transfer generator power to the coach. During the removal of the faulty transfer switch, I discovered that one of the 3 wires coming from the shore power input had a 2 inch section of melted insulation due to overheating. All of the connections were tight, but I can't determine what caused the overheated wire. The wiring coming out of the transfer switch to the coach were fine. Anyone had similar issues? Thanks, Matt

[atom ant]

Do you remember the color of the wire?

If it was white - it is almost always because it was loose so I would be stumped. If it was red or black, then that leg has probably been running overloaded.

I had a 2014 with an Onan 5500 (I really hope it wasn't mine!!, but I don't recognize the name). When I put the progressive dynamics surge suppressor in there, I was able to read how many amps were used on each leg, and it was balanced pretty well, but that doesn't mean they are all the same. You could have all the high draw stuff on one leg, and the other is lightly loaded.

I would definitely install a permanent surge suppressor just to see what is going on and be able to monitor it. If you see higher draw on one leg vs the other, you can balance it better by switching swapping out breakers to balance it out.

[XCMARK]

Originally Posted by mfsmith57

Hi Members, I recently purchased a 2014 Redwood 36RL, and I have the 5.5K Onan generator. During my first camping trip, I had an issue with the transfer switch, where it would not transfer generator power to the coach. During the removal of the faulty transfer switch, I discovered that one of the 3 wires coming from the shore power input had a 2 inch section of melted insulation due to overheating. All of the connections were tight, but I can't determine what caused the overheated wire. The wiring coming out of the transfer switch to the coach were fine. Anyone had similar issues? Thanks, Matt

several things contribute to wires burning . After something burns up its almost a 100% chance that the binding screw will be stuck and feel like it was tight. the internal contacts on transfer switch can be a cause or it could have been over tightened at the time of install causing the screw to strip or it can twist the contacts on the inside to not land square causing the contact area to be reduce causing it to heat up. I have been a formen for a large electrical contractor for 35 years , and have see the effects of poor installs on every type of electrical connections you can imagine and the #1 cause is the cable is left too loose . If the binding screw is burned and the wire is burned and nothing in the case past the connection is burned as bad you have a loose wire. If its burned inside the case and outside at the connection then it was the contacts in side .

[mfsmith57]

Thanks for all of the information. I'll let you know what I find out when the new transfer switch is installed.

[XCMARK]

Originally Posted by mfsmith57

Thanks for all of the information. I'll let you know what I find out when the new transfer switch is installed.

pictures are the best way to see what happened . Best of luck, hope its a fairly quick and easy job!

[mfsmith57]

Folks, I couldn't figure out how to upload photos here, so I created a photo album with the pictures of the transfer switch and the wiring after I removed it.

[RollsRoyce]

How do I get a look at the pictures of your transfer switch wiring

[mfsmith57]

Click Photos on the top of this page, and look for the uploaded photo album with the same title of this thread.