Only getting 30A when plugged into 50A

[rkdillinger]

Originally Posted by windsorbill

I would not replace a relay in that box. Replace entire ATS. You're lucky it didn't start a fire.

https://www.rvupgradestore.com/LYGHT...yABEgLwD_D_BwE

It's best to turn off large load items such as roof airs before you switch from shore to generator power. The ATS is taking a big 'hit' every time that power is swapped over under load.

Yes, that plastic cover was melted and warped and sagging down. At some point it could have ignited and caught fire. I've found a mobile RV tech that happens to have this ATS, so we're headed over there to pick it up now so I can replace the entire thing.

I have no way to switch from shore power to generator power when I'm connected to shore power as the generator will not start. I have to shut down the shore power connection before the generator will even start. And the strange thing about this issue is it happened when we were gone, so nobody was messing around with anything when it happened. Crazy!

Thanks everybody, I should have the new ATS installed in a few hours!!

[windsorbill]

Originally Posted by rkdillinger

Yes, that plastic cover was melted and warped and sagging down. At some point it could have ignited and caught fire. I've found a mobile RV tech that happens to have this ATS, so we're headed over there to pick it up now so I can replace the entire thing.

I have no way to switch from shore power to generator power when I'm connected to shore power as the generator will not start. I have to shut down the shore power connection before the generator will even start. And the strange thing about this issue is it happened when we were gone, so nobody was messing around with anything when it happened. Crazy!

Thanks everybody, I should have the new ATS installed in a few hours!!

get that ATS switched out and see if the "genny no start" is still an issue.

[rkdillinger]

Originally Posted by windsorbill

get that ATS switched out and see if the "genny no start" is still an issue.

Sorry, I wasn't really clear. The generator is designed to not run if I'm connected to shore power. If I try to start it, it fires up and then immediately shuts down. If I disconnect from shore power it fires up normally.

Regarding the ATS: I found a used replacement that probably would work, but it's physically very different and I don't believe I have enough "slack" in the power cables to re-configure everything. For the time being I have bypassed the ATS completely...now the shore power goes directly to the breaker box and everything is fine. I'll be ordering an exact replacement ($300-$400) and install it when I get back home.

Thanks again everybody for all the help!!!

Randy

[Archer2]

Originally Posted by rkdillinger

Sorry, I wasn't really clear. The generator is designed to not run if I'm connected to shore power. If I try to start it, it fires up and then immediately shuts down. If I disconnect from shore power it fires up normally.

That’s really kind of strange. Why would you want the generator to not be able to start if you were plugged into shore power? Are you sure that the behavior of the generator (ie would crank & start but then quit) is not possibly connected to the ATS failure? If everything is working like it should the generator would be completely disconnected from any path to the shore power and thus would not have any way to be aware that the shore power was connected. I would be leaning toward the possibility that when you start the generator with shore power connected as well then the ATS senses that the Gen is running and after a short delay the ATS logic commands the relays to switch to the generator, but one of the relays is defective and doesn’t switch cleanly and completely. That leaves the generator output either shorted or connected to one leg of the shore power and that faulty switch causes the Gen to shut down.
The worst part of that is if the ATS fails in such a way as to allow the generator output to be connected to the shore cord after switching to generator then while that condition exists the exposed male shore power connector plug could be energized with 120VAC. Very dangerous!

[rkdillinger]

Originally Posted by Archer2

That’s really kind of strange. Why would you want the generator to not be able to start if you were plugged into shore power? Are you sure that the behavior of the generator (ie would crank & start but then quit) is not possibly connected to the ATS failure? If everything is working like it should the generator would be completely disconnected from any path to the shore power and thus would not have any way to be aware that the shore power was connected. I would be leaning toward the possibility that when you start the generator with shore power connected as well then the ATS senses that the Gen is running and after a short delay the ATS logic commands the relays to switch to the generator, but one of the relays is defective and doesn’t switch cleanly and completely. That leaves the generator output either shorted or connected to one leg of the shore power and that faulty switch causes the Gen to shut down.
The worst part of that is if the ATS fails in such a way as to allow the generator output to be connected to the shore cord after switching to generator then while that condition exists the exposed male shore power connector plug could be energized with 120VAC. Very dangerous!

Good point, and good question. I've never tried to start the generator while on shore power, so don't really know the answer. When I get the new replacement ATS I'll get it installed and give it a shot (the next time I get to a 50A supply )

Thanks!

[shootist]

My gen definitely runs fine while on shore power. I never unplug when I exercise it. I also always take the load off before starting and stopping it.

[wolfe10]

Originally Posted by shootist

My gen definitely runs fine while on shore power. I never unplug when I exercise it. I also always take the load off before starting and stopping it.

That is not "best practices", though it can be done.


First it is very hard on the points in the ATS to transfer under high load.


Also, not so good on the generator to go from stopped to high load quickly. Kind of like starting your car cold and immediately going to 70 MPH.


Best practices is to shut off high amp loads while on shore power.


Turn off shore power breaker and then disconnect shore power (this step is optional)


Start generator and let it warm up for a few minutes.


Gradually add load until 50% plus of capacity.


Run 30-45 minutes.


Turn off loads and let generator cool down for a few minutes before shutting it off.


Plug back into shore power, turn on breaker and turn back on loads.


Can you ignore all the above-- of course. It IS your RV.

[Archer2]

Unless I read it wrong I think that Shootist described that he does follow the same procedure that you advocate.

[153stars]

I was able to find a relay that fit my Lyght type ATS for about $45 on eBay. Then was able to get the single hinge part on old one to work as intended in a few minutes. This fit mine was sent a $10 price reduction after I put on watched list there's best offer. I'm not sure if exact same as yours. These single bar type seem to hum less
https://www.ebay.com/itm/12192517164...mis&media=COPY
If not mentioned ATS should be checked yearly for melting or loose connections. The more you use MH and pulling high amps, like full timing the more often should be inspected. Seems pretty common to need repairs where actual wires are tightened down. Less issues with the factory UL crimped wire loops and screws.

[jcrowder3]

We had a similar problem. Turned out the relay in the transfer switch that moved the L2 was carbonized. Replacing the transfer switch fixed it. We had one from light systems if I recall and it was easy to see or test once you opened it up.

[dickb46]

My 10 cents.
Looking at the picture and the damage to the wire; it looks like the incoming wire was receiving all the damage from the heat/high resistance.
From that I would put the fault for the damage on the incoming wire at the connection going into the transfer switch. I'm not suggesting that the switch isn't bad but just check the incoming wire for corrosion or frayed wire.
dick

[Archer2]

Originally Posted by dickb46

My 10 cents.
Looking at the picture and the damage to the wire; it looks like the incoming wire was receiving all the damage from the heat/high resistance.
From that I would put the fault for the damage on the incoming wire at the connection going into the transfer switch. I'm not suggesting that the switch isn't bad but just check the incoming wire for corrosion or frayed wire.
dick

Yup, 100% agree!

[Surf Fisher]

Direct replacement transfer switch, $256.

https://tinyurl.com/243v3acm

[rkdillinger]

Originally Posted by Surf Fisher

Direct replacement transfer switch, $256.

https://tinyurl.com/243v3acm

Thanks, we'll be ordering soon!

Thanks everybody!!!