Another electrical problem with 50 amp service

[jclarkfork]

My MO is 50 amp service. We were camping in a state park with 30 amp service with a GFI at the electric box. When I would plug in with my 50 to 30 amp adapter and then turn on anything in the MO the GFI on the pedestal would break. Finally had to move to an empty Host spot with 50 amp service and then no problem. Have never had to problem with 50 to 30 before but this is first time with a GFI at the pedestal. Any Idea's

[RustyJC]

Originally Posted by jclarkfork

Have never had to problem with 50 to 30 before but this is first time with a GFI at the pedestal.

You likely have a small current leak to ground, probably through an electric water heater or refrigerator heating element, that the GFCI is seeing. If the hot leg current and the neutral leg current are not identical, the GFCI will trip, so a little leakage to ground will cause this problem.

Rusty

[FlyingDiver]

We have problems with GFIs even on 50 amp circuits. GFIs are really problematical when there's a complex load, like an RV with it's own service panel and multiple devices.

joe

[ArmyEOD]

Originally Posted by jclarkfork

My MO is 50 amp service. We were camping in a state park with 30 amp service with a GFI at the electric box. When I would plug in with my 50 to 30 amp adapter and then turn on anything in the MO the GFI on the pedestal would break. Finally had to move to an empty Host spot with 50 amp service and then no problem. Have never had to problem with 50 to 30 before but this is first time with a GFI at the pedestal. Any Idea's

Sir, if I am reading this right, you are saying that the camp ground power pole had a GFIC on the breaker for the 30 amp plug mounted in the camp ground box and it would only trip when you turned something on in the RV is that right? Was there anything at all running ie converter/inverter prior to turning on an item? Or would it trip when you turned on your main breaker in the RV. Just trying to help sort it out.

George

[jclarkfork]

Originally Posted by ArmyEOD

Sir, if I am reading this right, you are saying that the camp ground power pole had a GFIC on the breaker for the 30 amp plug mounted in the camp ground box and it would only trip when you turned something on in the RV is that right? Was there anything at all running ie converter/inverter prior to turning on an item? Or would it trip when you turned on your main breaker in the RV. Just trying to help sort it out.

George

You are correct, the converter was running and the clock of the Microwave would work, but If I tried the Micro or the refrig it popped the GFCI at the pole not in the MH. There was a 45 DP next to me and he was hooked up on the 30amp I presume. He was not there so could not talk to him. Some times it would break as soon as I turned on breaker at the pole, other times that would be ok until I tried the micro or refrig inside. Finally gave up and moved to a 50 amp site without a GFCI on the pole and no other problems. Also, come to think of it I have plugged in my 15 amp extension cord in my shop to a Gfci plug and that also will break it. If I plug into another plug not on the GFCI circuit I can run most everything in the MH on the 15 amp except the AC. Normally just keep it plugged in to keep the battery's charged.,

[Pusherman]

John, I too am confused by your problem. To my knowledge there are no GFI 30A circuits at campgrounds. Only 15/20A circuits on GFI. The 50A and 30A circuits on the pedestals at campgrounds are not protected by GFCI.

If it was a 20A GFCI receptacle, then that may make a little more sense.

Here's my theory, if you were in fact plugged into a 20A GFCI receptacle.

RV's are wired differently than houses, in that the grounds and neutrals are split at the RV panel, with both ground and neutral wires going back to the campground pedestal.

You may have a slight voltage leak in the RV, meaning a slight short to ground, which is causing different voltage between the neutrals and ground circuits in the RV. If you're plugged into a (20A) GFCI receptacle, since they measure voltage difference between neutral and ground, it will pop the GFCI, but not necessarily the circuit breaker.

When you're plugged into a 30A or 50A service w/o GFCI protection, the slight voltage leak may go undetected, and never cause a circuit breaker to pop.

You may still have a problem in your RV, though.

[TQ60]

Simple problem...difficult to remidy

The GFI device bei it a unified outlet or built into a breaker is a relativly simple device, it looks at the current flow on the main wire, L1, HOT or BLACK, and compares it to the current flow on the return, neutral or White wire.

If it is the same on both wires it is happy, of it is less on the White then on the Black then some of the current is flowing to a ground someplace, possibly via your wet foot.

Sometimes the GFI device is bad, other times is is a leaky cord or bad connection.

You can troubleshoot this at home, start with pluging your MH into a GFI outlet or picking up a cord with one built in, or you can build your own with a heavy duty extension cord and the parts.

Before you make any repairs test first to insure you can repeat the problem, then start checking connections, open your ac distribution system and make sure someone did not connect a green wire to white buss, or a white wire to the green buss, or a wire between them.

With the coach unplugged tighten all grounds (greens) and returns (whites)
Retest after small things so yo know when it started working.

Check your fridge to make sure no pinched wires, a wite to green pinch will work just fine as they both are connected AT THE METER, but they will trip the GFI in an instant.

Wet outlets also will do this.

Happy hunting!

[wa8yxm]

If you are plugging a 50 amp Motor Home into a 30 amp outlet using a dogbone and you turn on everything in the coach it is the circuit breaker that will trip, not the GFCI, assuming everything is properly operating. Now the only 30 amp GFCI's I have seen have also been circuit breakers.. In my case I knew why it was tripping. (Ground fault or over load) but unless you know the cause, it can be hard to discover.

Now, the other option is if you use one of those cheater boxes to plug into both the 30 and 20 amp (Usually GFCI) outlet.... The GFCI is supposed to trip, 100% of the time, which is why I advise AGAINST those boxes.

[jclarkfork]

tks all I will start tightening things up and see what happens

[PatStab]

I stayed at a campground a last year and it was 30 AMP with a GFCI. Soon as I plugged in the breaker flipped. I got the campground guy and he replaced the GFCI and said I had problems in my motorhome, had to run the genie for awhile.

I went on on my trip and never had the problem anywhere else, never had it before. Whatever was wrong was in that campground, also it was pretty full.

[wa8yxm]

Many have repiorted issues with the fridge heat element or the water heater element, The Microwave, not so much.

I still think he is tripping the breaker, not the GFCI, but I an not "eyes on" so can not be sure.

The GFCI is kind of a teeter totter, (Or balance if you like) it measures current in the HOT and in the NEUTRAL, and of one wire is running "heavier" than the other TRIP it goes,.


Thus, if it is tripping you either have a short to ground, or a "Phantom" neutral somewhere.

This is why the dual 30 amp to 50 amp cheater boxes will NOT WORK with a GFCI... There are two "hots" and one "neutral" so the current never balances.

[Dave78Chief]

Here is a good write up about campground GFCI problems in an RV (give credit where credit is due ):

Re: Plugged in tripping GFCI circuit

Additionally, GFCI recepticles in the rig have been known to trigger the campground GFCI breaker.

Some nice to know GFCI information: Ground Fault Current Interrupters

Given that in your situation the source GFI breakers (campground and home circuit) are tripping, I have a fairly good hunch you do have some sort of a problem (either a Hot to Ground or Nuetral to ground short). You do not see the problem when hooked to 50 amp service because they are not using 240VAC 50 amp GFCI brakers. The GFCI breaker is trying to tell you something is not quite right.

One thing that gets overlooked with RV's is that an RV is considered a subpanel to the shorepower distribution network. While we may be accostomed to seeing the nuetral and ground leads connected together in the our Main Stickhouse AC Panel, a subpanel (like an RV) cannot have the nuetral and ground leads connected together. If nuetral and ground are connected together in the RV, it will always trip a shoreside GFCI breaker.

Dave

[85antique]

I had the same problem i found a bonding jumper in the panel of the mh it jumps neutral ( white) to ground (green or bare ) removed it all is good no more pedestal gfi trips unless the dog bone it out in the rain just as stated above it is a sub panel and not required