30amp to 15amp adaptor

RCB · 05-12-2021, 06:34 PM

I have tried two adaptors and every time I plug them in to a 15 or 20amp plug it trips the breaker of the plug. Could I have two bad adaptors? The 2nd one is brand new. I have turned off the coach switch, disconnected microwave and made sure everything is off. Any ideas?

Morich · 05-12-2021, 07:10 PM

A breaker is meant to trip when we pull more current than that circuit is designed/wired to carry. So if you are plugging an adapter into use 15 amps and actually are pulling 20 or more on a 30 amp RV, the breaker should trip.

So we need to be clear on what you are doing about turning off the equipment. Do you mean you have turned off the equipment and THEN plugged and the breaker tripped? Or do you mean it tripped and you turned things off after?

Bones2003 · 05-12-2021, 07:29 PM

RCB,
I noticed on a thread you started on 12-18-2020 that you reported your 30Amp breaker was tripping. Did you ever resolve that problem? If your 30A breaker trips when connected to a 30A source then your coach will never operate on 15A.

RCB · 05-12-2021, 07:40 PM

I turned everything off before plugging in. I use to plug my 50amp fifth wheel all the time to 15 or 20amp with no problems. No I don't have a problem with the 30A breaker tripping. only when I have to many things going at one time.

imnprsd · 05-12-2021, 10:44 PM

The why in interpret RCB's problem is like this:

* His RV has a 30A plug and he bought an adapter so he can plug into 15A or 20A power, which is a standard wall outlet socket.

RCB, if you look closely at your wall socket (recepticle) and see a horizonal like through on side, this designates you are plugged into 20A power... if they wired it to standards. Otherwise the CB in the house going to limit your power consumption to 15A, more or less.

What you did not explain is if you are using a 50' foot exension cord? If so, the line is too long for 14A extension cord types and you might try a 12 gauge extension cord to keep the CB in the house from popping.

...Of you might just have a weak CB in the house.

RCB · 05-13-2021, 06:25 AM

I used a 15ft cord, I had the same problem at a campground without using an extension cord.

Morich · 05-13-2021, 07:12 AM

With those details, I would suggest there are two likely causes.

First and more likely is that the breaker has trips too often and has become weak, so that it trips too easily. Very common.

Second and less likely is that there is an honest problem with some part of the RV power, shorting to ground. I feel this is unlikely but possible because a short to kill a fifteen amp breaker would be expected to also do a lot of arcing to be noticed right away.
It is possible for multiple items in the RV to be pulling too much power and add up to enough to kill the breaker but that should be something you would know. One way to rule this out would be to turn all the breakers feeding the inside circuits off and then slowly turn them on until it trips. Give some time after turning each breaker on to allow for it to heat as normal.

For testing with actual numbers to guide you, a Kill-A-Watt meter can be a worthwhile gadget to help as it can be simple to plug it into the 15 amp outlet and then the adapter to the RV into the meter to show actual load.

But my main bet would be on a weak breaker.

Marine359 · 05-13-2021, 07:13 AM

Quote:

Originally Posted by RCB

I have tried two adaptors and every time I plug them in to a 15 or 20amp plug it trips the breaker of the plug. ?

Is the “plug” you’re referring to here the plug on the campground utility post or home circuit, or the 30amp shore power breaker in the RV cb panel?
If you turn everything off in the RV by switching off the breakers, you can calculate how much amperage you are drawing through each breaker on the cb panel. Using dc circuits should not trip any breakers unless you have the furnace, wh and tank heaters on at the same time. If dc is off, turn on each of the high amperage ac circuits one at a time until trip then calculate total amperage being used. If it trips at a very low amperage use, my next check would be a possible faulty or loose shore power breaker. I’ve been at campgrounds where my 10amp battery charger will trip the post breaker.

rprochnow · 05-19-2021, 04:26 PM

Are there any problems when connecting to 30A power?

For testing purposes, recommend throwing all of the 110V breakers inside the coach and turn off the inverter. Also turn off all of the 12V devices (refrigerator, A/C thermostat, exhaust fans, ...).

If 30A power works and 15/20A power doesn't and this happens with multiple adapters at multiple locations, then probably something inside the coach that is pulling more than 15/20A (even if it is a surge, like when A/C starts up).

If it fails, it could be battery charging. If there's a battery disconnect for the coach and/or chassis, try disconnecting the batteries - and run a test. That would rule out battery charging as a cause.

sgtstriker · 05-19-2021, 05:15 PM

Converter/Charger? Just a thought.....

RCB · 05-19-2021, 08:25 PM

The next time I get it out of storage I will try all of the above. thanks for the suggestions.

jerichorick · 05-22-2021, 06:55 AM

Quote:

Originally Posted by RCB

The next time I get it out of storage I will try all of the above. thanks for the suggestions.

I see many good suggestions above. This may be redundant. I strongly suggest that you open up your ATS and check the connections there. Also, if this all looks good, remove the shore cord wires from the ATS terminals. Test the cord with an ohm meter. You could have a damaged power cord. If everything is off, no power demands when plugging in, there must be a short circuit back toward the rv.

DryCreek · 05-24-2021, 05:44 PM

I read his problem to be the circuit breaker in the supply to the 15 amp outlet is tripping.

If it's a GFCI, that's your problem. Those do not like the bonded neutral an RV has.

RCB · 06-04-2021, 10:24 AM

Ok I turned off all breakers in the rig except for the main, plugged it into a different 15A plug and it tripped the gfi as soon as the plug made contact, tried a different 15A plus and it did the same. So what is everyones thoughts.

imnprsd · 06-04-2021, 11:55 PM

DO YOU HAVE POWER WHEN THE GENERATOR IS RUNING?

If you don't then the following information may help.

If you do have power in your RV, with the generator running, maybe your ATS neutral relay has gone bad or is sticking.

If it's not your ATS then maybe the following information will help

===

So you house 15A breaker keeps tripping no matter if you have zero amps of load. ...No matter if it is a GFI socket or not? ...Sounds like a neutral wire problem to me.

==> Before you go looking for a bad neutral wire, I suggest you inspect your main circuit box and tighten your neutral (big wire) lug... and then retest.

...Still blowing the CB in the house? ...Try tightening all the all your other black and white wires lugs that are lose.

Note: You only have a bonded neutral to ground in the RV when you use generator power. I.e., all shore power connections are bonded at the power source.

IF MORE TESTING IS NEEDED

* With no power to the coach... do a continuity test on your power cord... touch the multi meter end of L1 to ground... and then your neutral wire to ground... neither test should beep.

If it beeps then you have a short to ground somewhere in your RV.

Note: Since you are blowing your house 15A breaker with all the black wire Circuit Breakers (CB) turned off, then I suspect you have a white-neutral-return wire shorting to ground in your RV.

Maybe the wire is rubbing on something...somewhere?

* First open the ATS and inspect for burn marks and for lose wire lugs. If all looks good then bang on your ATS box with the hope you can free up a burned relay point contact inside... behind the plate you cannot see. This is where your ATS-relays are located.

What type of ATS do you have?

* Remember, all neutral wires are connected; and when you open your main circuit panel you will see them all connected to a single buss bar just like in your house. So if one neutral wire is shorting out to ground then you need to find that wire.

How?

With no power connected, verify your neutral bus bar to ground beeps when you do a continuity test. This is how you know your neutral wire is shoring out.

Now start removing 1 neutral wire at a time until the beep stops. ...And that's your bad wire.

Note: Your continuity setting will time-out after a while so you may need to reset it. Also it helps if you have alligator clips to your multi-meter so your hands are free to pull one neutral wire at a time.

Good luck and keep us posted.

DryCreek · 06-05-2021, 07:24 AM

GFI will not work with a bonded neutral. Period.

jerichorick · 06-05-2021, 08:51 AM

Quote:

Originally Posted by RCB

Ok I turned off all breakers in the rig except for the main, plugged it into a different 15A plug and it tripped the gfi as soon as the plug made contact, tried a different 15A plus and it did the same. So what is everyones thoughts.

If you plug into a non-GFCI do you trip the circuit breaker?

You CAN NOT use a GFCI outlet or circuit on your RV. WILL NOT WORK. Many have already stated this. (Definition of insanity: Doing the same thing over and again expecting different results.)

Mtn Charlie · 06-05-2021, 11:13 AM

Most home outside plugs are GFI. They are usually down stream from a GFI receptical inside the home or a GFI breaker.

RCB · 06-05-2021, 03:08 PM

I opened up the ATS and the plastic on the terminal block where the neutral of the cord is attached was black, I removed the wires from the cord, cut them off, stripped them and put them back in. Is this enough or should I replace the ATS? It was working fine hooked to 30A.

Rsnook · 06-05-2021, 03:35 PM

Check house and see I find you have a gfi mine was doing that and could not figure it out and then one day!!!