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jondrew55 · 03-27-2017, 11:52 AM

As mentioned in an earlier post I now have a covered parking spot with power. It's only a 15 amp line, but is sufficient to keep the batteries charged and when needed, keep the fridge on.

When I went to get my rig ready for our recent trip, I noticed the 110 was out and the GFI at my storage had tripped. No idea why. I brought my rig home that night, plugged it in (using a 4 prong 50 amp to 30 amp adapter and then a 30 amp connector to std 110 plug adapter). About an hour later I went to the coach and the power was out. The GFI at my house had tripped. After some experimenting I realized that if I kept the main disconnect to my inverter in the off position, the power stayed on fine. If I turn the disconnect on such that the inverter is powered up, the house GFI eventually trips after a while.

While camping (on 50 amps) I had no problems at all. Not sure I can figure out why the disconnect for the inverter would trip the GFI. I get if the I verer drew too many amps the house breaker would trip, but in this case it's only the GFI tripping. Other than that everything seems normal.

Gary RVRoamer · 03-27-2017, 01:34 PM

When you plug to a 50A outlet, it has no GFCI protection so no tripping.

A ground fault occurs when some appliance or circuit allows some current to flow to either the ground wire or the RV chassis (which in turn is wired to the 120v ground wire). If there is a GFCI somewhere in that path, it will detect the ground fault and trip.

I'm not sure what you mean by the "main disconnect to the inverter", but if the inverter receives no shore power, it cannot pass any through to the RV's branch circuits so any ground fault in the wiring or appliances on those circuits cannot happen. But if the inverter is actually disconnected from shore power, it can't charge batteries either. Could you be a bit more specific about what inverter make/model you have and what you are turning off?

jondrew55 · 03-27-2017, 01:46 PM

Up in the cab by the front door are two disconnect switches. One for the chassis power and one for the hose batteries. They are small rocker switches and I assume power larger relays somewhere in the back. But even with those off the inverter (I believe it's a Magnum 2800) goes into sleep mode and still will drain the battery. In order to prevent that there is a large manual disconnect switch in the house battery compartment that disconnect the inverter. When that switch is in the on position, my home outlet GFI eventually trips (no appliances I know of are on). When the switch is turned off the coach does not trip the GFI and the battery charger circuit keeps the batteries charged.

Quote:

Originally Posted by Gary RVRoamer

When you plug to a 50A outlet, it has no GFCI protection so no tripping.

A ground fault occurs when some appliance or circuit allows some current to flow to either the ground wire or the RV chassis (which in turn is wired to the 120v ground wire). If there is a GFCI somewhere in that path, it will detect the ground fault and trip.

I'm not sure what you mean by the "main disconnect to the inverter", but if the inverter receives no shore power, it cannot pass any through to the RV's branch circuits so any ground fault in the wiring or appliances on those circuits cannot happen. But if the inverter is actually disconnected from shore power, it can't charge batteries either. Could you be a bit more specific about what inverter make/model you have and what you are turning off?

jondrew55 · 04-02-2017, 02:34 PM

Bumping this thread hoping to get more info.

First, my inverter is a Magnum MS2812 2800W inverter. If found the full manual for my inverter here:

http://www.magnum-dimensions.com/sit...ies%29_Web.pdf

Second, back in the battery compartment, there is a master battery disconnect switch (manual). As far as I can tell, when you turn this to the off position, the battery is disconnected from the inverter.

Gary RVRomer pointed out that there is no GFI protection when plugged into a 50 Amp connection. Not sure what happens when you put a 50 Amp to 30 Amp converter, and then add a 30 Amp to standard house 15 amp connector. When I plug into a standard outlet using that combination, I eventually trip the GFI on whatever I'm plugged into (either my house or the outlet at my storage lot).

I went to check on the RV today, and it appeared the 110 was completely off in the coach, even though the GFI had NOT tripped. The Magnum inverter remote control had a red light on with the message "dead battery". I had the manual master disconnect in the off position. I'm thinking the auto sense circuit on the magnum was seeing less than 5 watts of power use, and dropped to "off" condition.

So I think there may be two seperate things going on here: First, when the inverter is hooked to the battery (main battery disconnect switch on), I'm suspecting that some circuit comes on (not sure what) that somehow leaks some current through the ground on my multi-adapter plug and pops the GFI. I'm thinking I could test this by cutting the ground prong off an adapter (possibly a dangerous thing to do).

The second thing happening might be with no current draw going, the Magnum is not sensing the need for power and the system goes into sleep mode and turns off the 110. (This is completely unrelated to popping the GFI). I could get around this by plugging something in that always draws more than 5 watts.

Ill give Magnum a call when they are open and see how their customer tech support is.

twinboat · 04-02-2017, 03:20 PM

The inverter you have is an inverter/charger.

When you disconnect the battery it can't charge or maintain the batteries. The internal transfer ( Pass Thru ) switch, in it, may also need battery power to funtion, so the 120 volt power may not go thru it. Basicly, it won't do anything.

After getting your batteries charged back up, so it doesn't trip the breaker for the 15 amp house line, I would leave the inverter battery switch on and start manually tripping breakers to find the one that is causing the fault.

Start with the Refregerator and or Icemaker.

jondrew55 · 04-02-2017, 03:25 PM

Makes sense. The fridge was off (breaker turned off). I'll turn everything else off at the breaker panel and then start turning g things on one by one till I find the culprit. Thanks

Quote:

Originally Posted by twinboat

The inverter you have is an inverter/charger.

When you disconnect the battery it can't charge or maintain the batteries. The internal transfer ( Pass Thru ) switch, in it, may also need battery power to funtion, so the 120 volt power may not go thru it. Basicly, it won't do anything.

After getting your batteries charged back up, so it doesn't trip the breaker for the 15 amp house line, I would leave the inverter battery switch on and start manually tripping breakers to find the one that is causing the fault.

Start with the Refregerator and or Icemaker.

winniman · 04-02-2017, 03:52 PM

Friend of mine parked in my driveway for the weekend with his C class. As soon as we plugged it in, it tripped the gfi on the outside plug of the house. I got a short heavy gauge extension cord with the ground plug missing. End of problem. Everything worked fine after that. I have the same problem sometimes on my garage plugging in the block heater on my backhoe. Same solution. A good sized cord with the ground removed. No ground, no gfi tripping.

jondrew55 · 04-02-2017, 03:56 PM

Might be my next step. Want to make sure I don't have an electrocution hazard first.

Quote:

Originally Posted by winniman

Friend of mine parked in my driveway for the weekend with his C class. As soon as we plugged it in, it tripped the gfi on the outside plug of the house. I got a short heavy gauge extension cord with the ground plug missing. End of problem. Everything worked fine after that. I have the same problem sometimes on my garage plugging in the block heater on my backhoe. Same solution. A good sized cord with the ground removed. No ground, no gfi tripping.

luvlabs · 04-03-2017, 07:35 AM

Motorhomes do not play well with GFI outlets as a power source. There is nothing wrong with your coach since everything works as expected when you are plugged into a non-GFI outlet or run the generator.

The reason for this happening is how the motorhome (and other RVs) handle ground. By code, your storage lot operator has to supply GFI controlled power unless... Power is delivered via a supply panel which has no requirement for GFI circuits.

Talk to the storage lot owner and explain to him that the GFI keeps tripping on the plug he supplies (you won't be the first one). Ask him if he could install a non-GFI circuit or a 30 or 50 amp supply panel for you. If he says no, then find a new storage area that understands RV electrical systems or install solar to keep the batteries charged and shut off the fridge in storage.

jondrew55 · 04-03-2017, 09:35 AM

Why not just cut the ground prong of an adapter to keep the GFI from tripping? A 30 or 50 Amp RV plug would be nice, but I just want power to keep the batteries topped off and to cool,the fridge off. This is one of the few covered RV lots in my area which was my main reason for storing here.

Quote:

Originally Posted by luvlabs

Motorhomes do not play well with GFI outlets as a power source. There is nothing wrong with your coach since everything works as expected when you are plugged into a non-GFI outlet or run the generator.

The reason for this happening is how the motorhome (and other RVs) handle ground. By code, your storage lot operator has to supply GFI controlled power unless... Power is delivered via a supply panel which has no requirement for GFI circuits.

Talk to the storage lot owner and explain to him that the GFI keeps tripping on the plug he supplies (you won't be the first one). Ask him if he could install a non-GFI circuit or a 30 or 50 amp supply panel for you. If he says no, then find a new storage area that understands RV electrical systems or install solar to keep the batteries charged and shut off the fridge in storage.

Gary RVRoamer · 04-03-2017, 02:33 PM

Quote:

Why not just cut the ground prong of an adapter to keep the GFI from tripping

That probably works, but not always. If the current loss is going somewhere other than the ground wire, the GFCI will still trip. As it should. But most RVs have minor leakage to ground and isolating the ground usually prevents the trip. Just pray you don't have a real short-to-ground emergency and someone gets shocked or killed.

Quote:

Motorhomes do not play well with GFI outlets as a power source. There is nothing wrong with your coach since everything works as expected when you are plugged into a non-GFI outlet or run the generator.

There IS something wrong with the coach if the GFCI is tripping. Maybe nothing very serious, but there is no reason that a correctly wired RV electrical system should be leaking current to the ground system. I'll grant it is a not unusual type of fault in RV systems, but it is not inherent. RVs should not trip GFCIs.