New camper electrical issue. Help!

[2021JayFlight28BHS]

Picked up the new camper yesterday, and I made the mistake of believing the dealer checked the electric.

Here’s the dilemma:

It’s 50amp

1 leg of the 50 amp works fine, it’s got the kitchen, fridge, bathroom, microwave, water heater, outside tv outlet and 2nd ac on it. The 2nd leg has the utility (read this as bedroom outlets, dinette outlets, TV outlet, outside fridge outlet), 1st ac, converter on it.

The 2nd leg drops voltage as soon as you turn the individual breakers on.... drops from 120v to ~ 30v when checking with multimeter, does this for the utility breaker or the ac breaker, or the converter breaker.

Does this mean I have a short somewhere on the utility or the ac runs? Maybe a screw thru it.... I’ve search as far as I felt comfortable.

There is a junction box for the utility run right under the converter where it branches 3 different ways... I guess I could take that apart and hook one up at a time until I find the issue on that run. And on the AC is there a junction box accessible that I can look at there?

Help, I’d rather not have to drag the camper 45 miles back to dealer if it’s something simple that I can figure out on my own as I’m pretty handy with electric and my multimeter.

Thanks in advance for any responses.

[Grumpy]

What are you plugged into? A house outlet or 50 Amp rv outlet?

[RipinSC]

Disconnect the shore power to the camper. Remove the cover from the breaker box and make sure the wire going into the breaker is secure. On my Eagle, one wire was tight in the breaker and the second wire was just sitting in the breaker and never tightened from the factory.

[2021JayFlight28BHS]

Thanks Grumpy for replying.
50 amp rv outlet at my house. It’s wired correctly. I am however running thru a 30ft camco extension cord to the Furrion 36 ft cord that came with unit. But at the end of both of these I’ve tested each leg and they are between 110 - 120v, only when I plug the twist lock end into camper and then turn main breaker and test at the individual breakers does it drop voltage and Only on the 2nd leg. 1st leg stays fine and everything on that side works.

Thanks RipinSC for replying.
I’ve tried retightening all screws on breakers, mains, neutrals and ground, flipping all breakers multiple times and checking fuses (I realize those are for 12v but I was desperate, lol).

Maybe I’ll pull cover of my main panel in the house and recheck those screws as well.

[ALJO]

It might not make good contact in the twist lock, some times one leg might have been hot. Therefore you have to check each connection. The problem is usual in the step back.

[JimD]

No short, which is a much overused term. The problem is resistance somewhere in the second leg feed. You are able to measure full supply voltage with no load but as soon as you put a load on it, the voltage drops because the lost voltage is going across the resistance. With no current flow the voltage will not be dropped across the resistance and show up as full voltage where you are measuring it.

Do you have a generator? If so, do you get the same readings? If yes, the resistance is internal to your rig. If no, the resistance is in your shore feed.

This will be a process of elimination. I would first temporarily connect to a 120 volt feed with an adapter. This ties both legs together and will tell you if the problem is internal.

As far as what would cause the resistance, the most common cause is a loose connection. This could be a screw connection or an outlet spade connection.

[2021JayFlight28BHS]

JimD,

You are absolutely right. I found a burnt spot on the 50amp breaker at the main panel... looks to have been a “used/return” but new to me breaker I picked up from Lowe’s....after switching this out. I reconnected everything including my surge protector. And Bob’s your uncle!

I had come to the conclusion I had lost my neutral on the main line coming in to my house and started metering every connection in my main panel and came across a lower voltage at the breaker. Pulled it out and found it had arc’d a bit. Crazy and scary at same time. Glad my camper wouldn’t quite work or I would’ve never found it and who knows what might’ve happened.

Thanks all who replied. Love this forum and it’s knowledge.

[2edgesword]

Glad you found this issue because my concern was fire. A 90V drop means a significant resistive load and heat.