Transfer switch burned - Again

No low voltage. It is always between 115-122. It does drop to the 115v range during the heat of the day. I have an EMS system that turns my power off if it ever drops to 104, but I would turn things off well before then.

Both failures are at multiple sites so one location isn't the cause. My EMS did shut off my power this past winter due to high voltage, above 132, due to a transformer failure from the power company.

Hi,

Are you monitoring voltage? If so, how low is it going?

I never ever start the generator when short power is on. I always turn off the breaker. I also never turn on power from either source when the a/c's are on and I eve turn off TV sets and satellite receivers. I full time so I do this a lot.

I checked the connection lugs for tightness just under a year ago and all were nice and tight and they were connected correct.

All three wires were burned, but worse on leg #1. I stripped the burned wiring back to undamaged before wiring to the incoming shore power leads. There isn't enough wire left to make the replacement and my dealer knows this and will be prepared to run new wiring to the breakers.

It seems like these switches just won't hold up to full time use.

What burned? Connection to the transfer switch or the contacts or some wire nut?

Sounds like a wire connection that was not properly installed more than the switch itself.

Have a pic?

AFAIK the PD53-100 is as good as they get.

pianotuna wrote:
Hi,

Once you are off warranty if the switch fails again, replace it with male and female plugs.

Or just buy a better quality contactor.

Hi,

Once you are off warranty if the switch fails again, replace it with male and female plugs.

Actually make sure the generator is off and your 50A service is off when making the switch. If either is on there will be arcing. Once switched to the new position then either trip the 50A breaker on or start the generator.

Transferring power with a load connected will cause the points to arc and eventually burn up. Make sure your A/C is off and any other high amp load.

Glad to hear that you had enough wire to work around the problem.

Chances are that someone did not tighten the lugs on the 50 amp connections properly the first time, and then the wire overheats. Now you might need to get rid of some very rigid and somewhat melted wire near the connections, so that the next transfer switch will work for a longer time.

Good luck! And be sure to inspect the job when picking up the RV. If it does not look like it was done right, you have the right and ability to make them fix it right. If the wires are melted insulation around them (discolored) all of that wire needs to be removed. Then large blue wire nuts and new wire is attached to the undamaged wire, and those new 12" - 18" wires would be attached to the replacement transfer switch.

Rated at 50 amps, it should not have been overloaded. Afterall you are not transferring loads while under loads, there really should not be more than 2-3 amps going through the switch when it transfers. All air conditioners should be off when you shut off the generator, and before turning it back on. When driving into a campground and ready to hook up, then the transfer switch would be in the unpowered 'off' position, so the contacts are already closed for shore to RV. It is once the generator is started, and then it will go through a 30 second waiting period that it will energize and move to generator to RV position.

You are not plugging in while the generator is on - are you? That is not good on the transfer switch or A/C units. Let the A/C units stay off for 3-5 minutes while shutting down the generator before plugging into shore power. .

Fred.