Possible electrical damage

[Kies277]

I changed over my home RV power pedestal from 30 amp to 50 amp. When I buttoned up the receptacle, my neutral wire popped off without my knowledge. I noticed some weird behavior from my AC units and then I heard loud electrical popping from the RV power center. There was a burning smell which caused great concern. I know the dangers of no neutral of 50 amp and the consequences, so I took everything apart. No breakers were tripped

The smell seemed to come from the converter. I repaired the outlet and checked all the appliances, everything was fine, thank God. The converter reads 13.4 volts at the battery wires with no power and 13.7 with power. Is that a pretty certain indication that it is fine?

I have solar as well, so the batteries charge regardless of the converter. I have not opened up the 2 battery boxes and disconnected the batteries to see if the converter is powering the 12V or not. Is that pretty much a "must do" at this point?

 

[Matt_C]

Kies,
You covered the specifics very well.
If everything works, you may have nearly dodged that bullet. Note: Nearly

I suspect that the converter has MOVs to protect it and they may have. If you crack it open, you may see a couple of things that look like ceramic capacitors. Or May Have - before they blew up. If you are a technical person or have a good friend that is, you may be able to replace them. (If the magic smoke leaked out, they are toast.) but the better idea may be to plan to replace the converter as a unit.

Matt

 

[Mark_K5LXP]

You're going to want to functionally test that converter before you can trust it going forward. That would include voltage regulation and power output over it's specified range. You didn't state the model of converter, if it's single stage this will be a straightforward test. If it's multistage you're going to want to monitor it over a complete charge cycle to make sure it's operating right. As far as 'wounded' parts go like MOV's, capacitors and such I would say to let that ride. It's a slippery slope to identify, source and replace stuff like that only to have some other latently wounded part fail later anyway. So, agree with Matt_C that repair by replacement would be the most efficient option if the converter is deemed unserviceable or it's merit is in doubt.

Mark B.
Albuquerque, NM

 

[Kies277]

I was gonna crack it open and look, but it is riveted. I ordered a new one, better safe than sorry. After I replace it I will open the other one up and see what's happening inside. Thanks for the quick responses.

 

[John From Detroit]

You don't mention the age of your rig but some converters today are "Switching Power Supplies" (my term for 'em Switching converters


The way these work. it might not matter if they get hit with 240 volt. in fact some plug in models the only difference between the US 120 volt and a European 240 volt models .... Is the plug. The supply itself auto detects (Well that's not precisely how it works) .. I would never count on such a thing however.

 

[Kies277]

I have a 2015 Crossroads Sunset Trail 5th wheel, the converter is a WFCO-WF-9865 65 amp converter.

 

[CharlesinGA]

This incident makes a good case for using a EMS unit, either portable or hardwired ALL the time. An EMS would have spotted that open neutral and not allowed any current into the RV.

Progressive Industries EMS-PT50X

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Charles

 

[Kies277]

I am acutely aware and have one now.

 

[John From Detroit]

Well K.. as they say Excellent.
I had the Surgeguard portable. when it failed I got the Hard Wired version.
Both work very well and Southwire has upgraded the warranty on the SurgeGuard models. My Hardwired outlived my RV. But that's not as impressive as it sounds.

 

[Kevin Means]

Whether or not your converter is damaged, will depend on its internal protections against high voltage. And FYI, a circuit breaker will not necessarily trip under high voltage - high amp draw and short circuits yes, but not high voltage.

I once plugged our RV into a 50 amp power pedestal WITH a portable EMS unit. Unbeknownst to me, the neutral ground wire in our power cord plug had come loose. Nothing happened until I turned on two of our three roof airs. Once they were on, the power imbalance, caused by the disconnected neutral ground wire, sent 240 volts throughout the RV. It caused a fire in our washing machine's circuit board, even though it was off. It burned up an armature in one of the roof airs - sending acrid smoke through the vents and it damaged the mother board in our residential fridge, which later had to be replaced. Fortunately, our Magnum Inverter/converter had built in high-voltage protection, so it shut itself down and was okay.

This all happened with a fully functional portable Progressive EMS unit plugged into the power pedestal. The problem with portable units is, the neutral ground wire in a power cord plug is downstream from the EMS unit, so the EMS unit can't detect it. It can only detect it in the power pedestal. Ours has since been replaced with a hardwired EMS unit, so the power cord plug is now upstream from the device.

Kev

 

[John From Detroit]

When that happned to me (loose wire in plug) Thankfully two conditions were different.
One: I'd hard wired by then
Two: Leg came lose not neutral.. Figured it out. next stop was a shop for a scheduled repair. I did the cord while sitting at the shop's outside picnic table.

 

[Kies277]

I replaced the converter and then took my old one apart. Everything looks good except this capacitor. It got blown out. Thank goodness that's all that blew.