HELP AC Outlets blowing devices!

[SDrummer]

Hello all,

I am currently living in a River Canyon 34RLQS0 5th Wheel that is hooked up to electrical power. I am having a odd issue with the electrical in the trailer. Some of the GFI outlets are blowing electrical devices when they are plugged in. Yesterday we plugged a toaster into the kitchen and it started smoking without even turning the device on. I also plugged my laptop AC adapter into the GFI outlet in the bedroom and it worked for about 2 minutes before blowing. The AC adapter does not give out any voltage and I verified this at my work.

The trailer has has issues in the past as it has blown the bedroom TV and kitchen Microwave as well.

I have measured the voltage on the plugs and they range from 110v-117v.

Today I tested all of the outlets with a GFI tester and they all read good indicating there are no line, neutral, or ground wires crossed.

The bizzare thing is that the plugs seem like they decide which devices they want to fry. I am currently running my heater and charging my phone on the same plug that blew my laptop AC adapter yesterday.

Any help is appreciated as I worried about plugging anything into the walls fearing it will blow the device.

Thanks

[wa8yxm]

WNJJ.. Id like to also congratulate you on an excellent post. Great job, I tried to describe my experience with a high resistance neutral at my house..

That is exactly what happened.

[CA_Traveler]

Since rig electrical systems bounce and vibrate down the road check ALL connections periodically. This includes all plugs, black boxes and panel. I've always found connections that weren't tight initially.

[randrx2]

wnjj wrote:

Great post! Good description of the issue!

[wa8yxm]

One thing I have seen in RV's (2 of them so far) that have Marinco inlets is screws loose, Check that make it 3 of them so far. Forgot one.

On a friend's RV it turned out to be one lead in the outlet (Cord end) that was not tightened down properly and the wire came out, You wiggled the cord and power was lost on that leg.

On the 5er parked in front of me at a COE park,, all six screws inside the cover were loose.. ALL SIX, the outlet fell off in my hand.

On my RV it was one of the INLET screws.... The dealer could not figure out hot to access them (I got it done though).

I am very fond of saying we RVers often have a few screws loose.. You have just read 3 examples of what I'm talking about.

I also had a bunch loose in the 120 volt power distribution panel, all 3 colors.

[BurbMan]

Any update?

[keepingthelight]

SCVJeff wrote:
You need to be looking at these outlets with a REAL load on them. If I were you and I had wiped out that much equipment, I would go to Home Depot and buy a 200-300w bulb and ceramic base, or better, a 500w construction service light. If you I kill it, who cares...

Anyway, if you have a loose neutral that opens under load, this is the only way you can see it... Loaded.

Personally I would start at the shore plug (that itself could be the problem) and check every single wire nut and push-in, or screw terminal of every plug in the RV. I have seen this before in a residential situation and it turned out to be a loose wire nut in a switch box tying a bunch of neutrals together, and it doesn't manifest itself until it's loaded up.

Or call an electrician, which BTW I disagree with the above poster on having only an RV tech look at it. There are wire monkeys and real electricians, that for this job are far more qualified and knowledgable about this kind of thing. These problems pop up in residential and commercial structures all the time, and the results are the same.

Totally agree with SCV Jeff. A loose connection under load is causing your problem. I have done electrical for over 30 years and yes this came be a very common problem. 😉

[BurbMan]

Poor contacts in the transfer switch would make sense...poor contact on the black leg would account for sometimes 117v and sometimes 0v readings, and poor contact on the neutral side would account for the intermittent high voltage. So you can have a situation where there is no contact on black or white and the red circuits are OK, but if the black makes contact without the white, that would give you the overvoltage that's frying the appliances.

[SCVJeff]

I would get into the ATS box and look at things in there. It seems to be a fairly common event for melt downs on the ATS box simply due to loose connections.

And, no. Losing one 'phase' (let's please not go through terminology again) will not cause the other side to rise, unless you have a neutral- hot reversal on that 'phase', and you have checked that, yes?

One thing at a time.. Find your black phase problem and then move on

[BurbMan]

Would it make sense to unplug from the house and fire up the generator and see what readings you get on the black wire here at the panel?

Process of elimination would tend to point to the transfer switch though...

[enblethen]

OP:
Your trailer is equipped with a genset?
You could have a bad transfer switch as the neutral and phase conductors are routed through one. You could have bad contacts.
Common trip breakers for shared neutrals have been around for some time. Somewhere in the late sixties early seventies.

[wnjj]

BurbMan wrote:
Common trip breakers have always been required on 220v circuits like the 50A here, but only recently (last couple years) required on split 110v circuits that share a common neutral. see diagram here, a different animal than a 50A circuit.

Somewhat recently, probably depending upon where you live. When I sold my 1978 house in 2003 the buyer's inspector marked down shared neutral (15A) circuits that were on seperate breakers. I replaced them with common trip ones.

[wnjj]

SDrummer wrote:
Sorry it took so long to reply back, I appreciate all the help.

So yesterday I opened the main circuit breaker box and found that the main black hot line is fluctuating between 0V-5V when in contact with neutral and ground. The red hot line reads great at 120v when connected to neutral and ground. I checked outside at the shorepower hookup and both hot lines are reading great at the receptacle. I also checked at the other end of the wire where it hooks into the trailer and both lines are reading 120v. There were 4 screws holding the receptacle into the trailer so I took that out and measured the voltage from the wires that are feeding into the trailer and everything is okay. I am guessing the problem is at the transfer switch where the shorepower meets the generator power.

There are 10 circuit breakers, 6 that are fed from the red hot line and 4 that are fed from the black hot line. All 4 that are connected from the black hot line are giving the bad voltage readings of 0-5V.

I have attached a picture showing the circuit breaker box. Circuits 3-4 & 7-8 are the circuits fed off the black wire giving bad voltages.

My question is does this explain the problem I have been having with the appliances blowing? Or do you guys believe I still have an open neutral somewhere?

Thanks

So are you saying the 4 circuits on the black wire don't even work at all?

An open hot (black) wire would make those circuits fail but would not cause the red side to rise. There must still be a neutral issue, IMHO.

[SDrummer]

Sorry it took so long to reply back, I appreciate all the help.

So yesterday I opened the main circuit breaker box and found that the main black hot line is fluctuating between 0V-5V when in contact with neutral and ground. The red hot line reads great at 120v when connected to neutral and ground. I checked outside at the shorepower hookup and both hot lines are reading great at the receptacle. I also checked at the other end of the wire where it hooks into the trailer and both lines are reading 120v. There were 4 screws holding the receptacle into the trailer so I took that out and measured the voltage from the wires that are feeding into the trailer and everything is okay. I am guessing the problem is at the transfer switch where the shorepower meets the generator power.

There are 10 circuit breakers, 6 that are fed from the red hot line and 4 that are fed from the black hot line. All 4 that are connected from the black hot line are giving the bad voltage readings of 0-5V.

I have attached a picture showing the circuit breaker box. Circuits 3-4 & 7-8 are the circuits fed off the black wire giving bad voltages.

My question is does this explain the problem I have been having with the appliances blowing? Or do you guys believe I still have an open neutral somewhere?

Thanks

[BurbMan]

Common trip breakers have always been required on 220v circuits like the 50A here, but only recently (last couple years) required on split 110v circuits that share a common neutral. see diagram here, a different animal than a 50A circuit.