Intermittent Transfer Switch Problem?

[CarlAda]

I'm experiencing an odd issue with my electrical system. I plug into a 50amp outlet and the power does not pass through to the coach. I start the diesel generator and I have power. After running the generator for a minute or two, I kill the generator and the ATS properly shifts power to shore power. This happened every time I plugged in during a recent trip.

I took the coach in for repair and he didn't experience the problem (isn't that always the case!). Anyway, he did find that most of the neutrals were burned while trouble shooting my rear air conditioner not working. I have no idea what could have caused the burned wiring. He repaired wiring, which also provided the proper amount of voltage to the AC unit. I took the coach home, plugged it in and no problems with power. Today, I pulled into Redmond Expo park, plugged into the power post and nothing! Jogged the generator and I have power again.

Has anyone ever run across a similar scenario?

I've yet to find the opportunity to troubleshoot with a multimeter, but I suspect that my ATS is the problem. Hopefully, the problem will manifest itself when I get home and I can possibly trace down the cause. If not, before I replace the ATS and hope that's the cause of my problem, does anyone have any other thoughts or ideas on what could be at fault?

50amp ATS, generator, portable surge protector (issue shows up with and without surge protector in use)

Carl

[dickandlois]

Carl,

From the information you posted, it sure sounds like the ATS. The fact that you can get power when using the generator and then the shore power works as soon as you stop the generator leads me to suspect the shore power contacts of the ATS have a carbon build up.

This can happen when high current items are not turned off before the coach is connected to the shore power. The carbon build up on the contacts isolate the circuit until you cycle it by using the generator.

The reverse happens when high current items are left on and one starts and stops the generator.

So, my vote goes to damaged contacts.

Rich.

[CarlAda]

Thanks for the reply Rich. I don't have any high current items on when I hook up, but the coach is only 6 month new to me and prior use of the coach is not known to me. Although it was low mileage (15K) when I purchased it, it is a 2008 unit.

[jlandon13399]

Carl,

If you find you have to replace the ATS please consider a surge protector if you do not already have one. I learned the hard way. They are available as portable or hard wired. I opted for the hard wired as I do not have to worry about anyone trying to steal it.

Good luck with your coach.

[CarlAda]

I have a Progressive Dynamics 50amp portable surge protector. I considered the inline hard-wired one, but the space was pretty tight where I would have needed to install and I'm sort of considering going to a new (new to me) coach within the next year or so.

Rich, considering carbon buildup, wouldn't that be a non event after a few cycles? I remember looking inside the switch and not seeing anything abnormal. I did check the tightness of all the connections and they were tight.

Can't imagine what else it could be. Guess I can double check the wiring between the cord plug in and the switch, but seems that if that were an issue that I'd see problems while hooked up and using shore power. When I get home, I'll do a complete check. With any luck, it will misbehave when I'm at home and have the time to do some voltage checking.

On another note, I drove an 06 Beaver Thunder 42ft today. My Seneca's a nice coach, but driving that made me realize that I would be so much happier driving a DP.

[kaypsmith]

Carbon buildup is mostly unseen. With no power on the coach, generator or shore power, one can use a piece of emorycloth,or sandpaper, 400 grit or higher and lightly sand both sides of the contacts, if they are accessible. Just a temporary fix, but will get you going till a replacement is available.

[CarlAda]

Thanks kaypsmith. I can try that when I get the coach back home from this trip .... I emailed Progressive Dynamics for their input.

[Walt2137]

Carl if you have to replace the switch check out the ESCO LPT50-BRD at about $150 I think ESCO switches are probably one of the best made.

[CarlAda]

I'll look into one, Walt. Any particular reason you find them better than PD?

[manholt]

Hi Carl, this is Carl.

Generator Joe is in California, Google them if you wish, they handle ESCO automatic switches....your question about ESCO being better than what you have? Don't know. I think it's like who makes the best circuit breaker, Pacific, Square D or Cutler Hammer?

Good Luck!

Carl C.

10' AMC Tradition 45'

Jeep Wrangler

[CarlAda]

OK...for follow up purposes and information, I have ruled out a bad ATS. I plugged the power in and didn't have power, so I took voltage readings at the inlet side of the ATS --- 000 --- I had previously double checked all of the fittings for tightness and they were satisfactory. Having established that the issue lay upstream of the transfer switch, I jiggled to cable (inside the coach side) where the power cable connects to to connector and could hear the power switch connect. SOOOOOOOO....that pretty much narrows it down to either the Marinco connector for the power cord or the connections of the cable within the connector.

Any other thoughts would be helpful, but it looks like I may just have to pull the connector at the coach and check the wiring and/or replace the connector completely.

Thanks for ALL of the above comments and suggestions!!!

Carl

[wolfe10]

Carl,

Good diagnostics. And, with a bad connection at one end or the other, look closely for signs of overheating-- burned contacts, melted plug, etc.

Brett