Visit our Popular Forums

chaseav · 07-08-2020, 07:45 PM

So I've read all the threads about the fridge tripping the breakers, shorting wires, GFCI's popping and all sound similar but the problem I'm having, whatever is causing it, is causing the 30 amp breaker (in my house) to trip not just the GFCI the fridge is on. When I run the fridge on DC, this doesn't seem to happen. The trickier part is that it doesn't do it immediately and can be reset, and it works again. Done this procedure a few times today.

It is "hotter than blazes" today in upstate NY but not over 92. The fridge has been working very hard and we are in direct sunlight for most of the day. After sunset now and it seems to be working fine...

Also, as a final clue; while inspecting the back of the fridge from outside the AS, I noticed a tiny bead of water running down the body of the fridge. May be normal and unrelated, but right below its path is the electrical "box" where all the wires connect to the fridge.

Thanks in advance! I'm 1.5hrs from any service so hoping for an on-site resolution!

BayouBiker · 07-08-2020, 08:14 PM

Do I understand correctly that it is tripping both the trailer 15A gfi breaker and at the same time the 30A standard service breaker in the house? I will assume the house has a 120V 30A two wire (plus a ground) RV connector and you are using a 30A cord to the trailer. The house breaker is not a GFCI breaker nor is the 30A outlet.

BayouBiker · 07-08-2020, 08:19 PM

I would guess the water is melting frost that has built up on the Freezer coils. It is melting because the refrigerator can't keep up in the heat. So first thing to do is to defrost the freezer as soon as you can to get rid of the water, which is almost certainly causing a ground fault. Next we will try to figure out how the ground fault also affects the house circuit without affecting the trailer master. I am thinking about that now..... but I need more info.

chaseav · 07-08-2020, 08:20 PM

Quote:

Originally Posted by BayouBiker

Do I understand correctly that it is tripping both the trailer 15A gfi breaker and at the same time the 30A standard service breaker in the house? I will assume the house has a 120V 30A two wire (plus a ground) RV connector and you are using a 30A cord to the trailer. The house breaker is not a GFCI breaker nor is the 30A outlet.

It's NOT tripping any sort of breaker or push button GFCI (if one exists on an RV) on the Airstream at all. I simply go into the basement and reset the breaker. And correct, the house has a 30 amp RV outlet I had installed by an electrician. As a maybe related side note, I've been on this hookup for about a week now, without issue until today, but the house is under construction and my 30 amp connection is only one of three circuits on the entire home system.

gator.bigfoot · 07-08-2020, 08:27 PM

Sounds like your circuit is overloaded. Put a clamp on amp meter on it and measure the load.

BayouBiker · 07-08-2020, 08:42 PM

Ok, so besides the frig, nothing else is on in the trailer, did I understand that correctly?

I'm with Gator, there must be some other loads on the breaker that is tripping. The frig has a 15 or 20 A fuse on the circuit board and a 15 amp GFCI breaker in the trailer power center so the frig cannot be drawing more than its rated 5 or so amps. If the water were causing a ground fault the breaker in the trailer would trip so the water is fresh an not causing a problem per se, though you should defrost it.

the rest of the trailer will draw 1-5 amps for normal stuff so lets say the trailer is max 10 amps but only for short periods. So we need to find another 20 amps of phantom load.

chaseav · 07-08-2020, 09:14 PM

Quote:

Originally Posted by BayouBiker

Ok, so besides the frig, nothing else is on in the trailer, did I understand that correctly?

Well, no. I had the AC running each time this has happened. I also discovered that my 11 year old had the TV outlet (Part of the GFCI loop) on a power strip with the TV, XBox and an unused device charger all plugged into it. He also plugged a night light and ANOTHER charger in under the kitchen. None of it being actively used at the times of incident(s) and I wouldn't think any of it adding up to enough amps to cause the entire 30 amp circuit to trip. Water heater, coffee maker, inverter, obviously microwave, all off and verified off. All non-essential (everything except Air Con, fridge and TV) systems currently powered off and all working properly...

chaseav · 07-08-2020, 09:17 PM

Quote:

Originally Posted by gator.bigfoot

Sounds like your circuit is overloaded. Put a clamp on amp meter on it and measure the load.

Good idea. Don't own one. Always wanted one just never needed it bad enough to spend the money. I just clamp it on the outside of the shore power cord...?

**GCinSC2** · 07-09-2020, 04:48 AM

Quote:

Originally Posted by chaseav

Good idea. Don't own one. Always wanted one just never needed it bad enough to spend the money. I just clamp it on the outside of the shore power cord...?

Not quite that easy. And if you're really serious look for a model that also does DC amps. Lots of stuff in the AS and TV could benifit from having the DC amp option.

https://www.youtube.com/watch?v=tpTjEighSak

gator.bigfoot · 07-09-2020, 05:46 AM

Quote:

Originally Posted by chaseav

Good idea. Don't own one. Always wanted one just never needed it bad enough to spend the money. I just clamp it on the outside of the shore power cord...?

Well the good news is that you can purchase these for a lot less than you think. Get one that is a true RMS. This is one tool you cannot do without. I have a dedicated one just for the trailer.

You will need to get access to the wire running to your circuit. But with a house breaker that is easy. In the modern trailers with the integrated electrical panel it will take some extra work.

Here is an example:
https://www.amazon.com/Extech-MA445-...294842&sr=8-15

**GCinSC2** · 07-09-2020, 06:08 AM

Another option and it has 600 amp AC/DC, temp probe and capacitance. The capacitance function can and for me has spotted a bad home AC capacitor. Temp probe, you'll be surprised at uses for that. About $130 online. I have model one notch below this one and missed the DC amp function. Drat.

https://www.homedepot.com/p/Klein-To...-206517428-_-N

RON NICKELS · 07-09-2020, 12:15 PM

There is probably not a problem with the fridge
It is the total of everything connected. My guess is that if you turn of the ac the fridge will run perfectly. Then you can turn on the ac and when it trips you can blame the air
conditioner. 😁😁

chaseav · 07-09-2020, 03:45 PM

Well, now over 24 hours since the first incident, everything seems to be functioning as intended. So the culprit is either a) the accumulated draw of all the silly things added up b) some sort of issue caused by frost accumulation / condensation on the outside coming into contact with something with a current running through it.

I don’t trust it!

chaseav · 07-09-2020, 03:48 PM

Quote:

Originally Posted by RON NICKELS

My guess is that if you turn of the ac the fridge will run perfectly. Then you can turn on the ac and when it trips you can blame the air conditioner. 😁😁

Couldn’t be! Because it was working fine in Gas (12v) mode. I could turn it back to Auto and within a short time 10-60 mins it would trip.

DaveG · 07-09-2020, 04:35 PM

A few related thoughts I hope are helpful: Your house breaker can trip from either temperature or over current. A breaker will get weaker after fault tripping. Some symptoms may be a smell, it feels hot, removing and inspecting it you find something odd like metal discolor or other. It is not a fact that a 15 amp breaker in line with a 30 amp breaker will trip first as breakers trip at different speeds depending on design. That is for example one may trip within 5 cycles and another within 2 (more or less). A GFCI does not trip on overcurrent, only fault current. Demand factor/timing: your AC and refrigerator attempt start at the same time, large surge. By design it is likely that your house breaker is faster tripping than the one in your trailer (but maybe not?). An AC current meter is clamp on while a DC current reading meter must be in series in the circuit. Always watch your voltage. If trailer voltage goes down more than 5% below your house voltage source the current load is surely going up. Beware of voltage drop. JMHO: If you spring for the DC current reading meter be sure it has internal fuse protection and is rated high enough in amps to be useful. Cheap VOM meters are for the most part just junk. You get what you pay for. Many off brand meters try to look like a Fluke but aren't even close beyond the look. Getting to know your meter and using it will enhance all of your electrical trouble shooting skills (if you stick with it). Meters can easily pay for themselves and save you much inconvenience.

SSquared · 07-09-2020, 06:13 PM

DaveG has a good point about watching the voltage in the trailer. If it is dropping a lot, there is a problem somewhere.

But DaveG is wrong on one point. While many clamp-type meters only read AC current with the clamp, other ones read DC current as well. I have a Klein meter that does both.

One other thought: Is the 30 amp outlet in your house the only thing on its circuit breaker? Are you sure the electrician did it right?

gator.bigfoot · 07-09-2020, 06:22 PM

In all the years that I worked on testing breakers and electrical equipment I have not witnessed that they get weaker with temperature. They are designed to withstand extreme temperatures and abuse. Heck we used to apply 33000 volts to them. Then they blew up. It doesn't rule out a defective breaker, but that is less common. Electronics can fail with temperature but we are talking about 55 Celsius and higher. Right now in the plant I have the high limit set at 45C since at 40 the limit was tripping and everything is running fine. And that's well over a million dollars in electronics.

gator.bigfoot · 07-09-2020, 06:29 PM

Klein is a decent brand. Not everyone needs the accuracy of a fluke. I've got my trusty fluke, but for on the road and elsewhere I have cheap ones. They work fine for the lower voltages. Just don't use them for high voltages. Most are not rated for that. But for a house or RV they get the job done.

BayouBiker · 07-09-2020, 06:57 PM

Quote:

Originally Posted by chaseav

Well, now over 24 hours since the first incident, everything seems to be functioning as intended. So the culprit is either a) the accumulated draw of all the silly things added up b) some sort of issue caused by frost accumulation / condensation on the outside coming into contact with something with a current running through it.

I don’t trust it!

Given your earlier descriptions of what was on and so forth, it is possible the the trailer was drawing 22-25 Amps. I doubt the condensation was drawing much if any as that energy wouldn't dissipate well and the board would show signs of heat buildup and it would more likely trip the GFCI.

If the house breaker is functioning as rated it is possible there was some other load on the house circuit accounting for the phantom 5-10 amps. Another possibility is voltage on the circuit is a bit low so the trailer was closer to 30 and the house breaker just happens to trip a bit sooner than the trailer main.

You may want to follow up on the low voltage hypothesis especially if you are certain there is nothing else on that circuit.

DaveG · 07-09-2020, 10:55 PM

Quote:

Originally Posted by SSquared

DaveG has a good point about watching the voltage in the trailer. If it is dropping a lot, there is a problem somewhere.

But DaveG is wrong on one point. While many clamp-type meters only read AC current with the clamp, other ones read DC current as well. I have a Klein meter that does both.

One other thought: Is the 30 amp outlet in your house the only thing on its circuit breaker? Are you sure the electrician did it right?

Hi SS, I yield on th DC clamp on, got that wrong, thanks for catching! Just getting too old I guess

However breakers do sense circuit temp and magnetic field. The temp is to trip before insulation melts (around 140℉ I think). Ambient temperature not much of a factor.