Breaker and ambient temperature

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Yeah I could see there is a space, but that doesn’t add capacity. My main concern is he’s asking way too much of this service box. I’d advise if car is charging, unplug entire trailer. And anytime trailer is plugged in, don’t have the car plugged in.

Even if his current problem is solved, this whole living arrangement has nuisance trips written all over it if you don’t do that.

A/C, car charger, fridge...that’s pretty much capacity right there.

Then you plug in your IPhone cuz you’re down to 3% and POP back at the 30 amp breaker that is located who knows where which feeds this box.

For the love of god he might even own a toaster! Or a coffee maker? A TV? Now what?

Now he’s totally dark until he can unplug and get access to the main panel for the park! Heckuva way to live. At least with his current problem he can just step outside and reset.

I know this sounds a little harsh but I’d still just run gasoline in the Clarity until I could move somewhere that gave me more electricity to use. This living arrangement simply is not friendly to owning an electric car.
 
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Thanks guys, interesting ideas. Next weekend will try to bring a thermal camera to see if any contacts are too hot.
Right now charging is out of the picture - running a/c is more important, and breaker cannot handle 18a continuous load.
The breaker on the right (with questionable wiring) is for my neighbor. I use it now for charging when he is not here.
My RV does not have any batteries, it has 110 to 12 v inverter for lights etc.
Regarding licensed electricians - I had to deal with some of them. Unfortunately these guys are very well trained for troubleshooting standard issues as well as building codes. But their problem is luck of understanding how it works and why as they typically do not have proper background education.
The best guy I met was an engineer back in eastern block, he got his license here, and it is a pleasure to work with him.
 
craze1cars said:
Also will advise that the whole repair could be as simple as tightening one loose screw...
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Definitely. Just yesterday I replaced a GFI outlet in a bathroom. Another outlet on the same circuit would not run an air compressor, which runs on every other outlet I’ve tried, including an outlet in the garage, protected by a GFI breaker at the main panel.

The “old” outlet, probably circa 1982, had stranded wire pigtails that were connected to the 12ga hardwire via wire nuts. One wire nut fell off and the wires disconnected when I pulled it out. On the new outlet the hard wire connects directly to the outlet. Voltage at the outlet was 120V but was not able to power a heavy load. Glad I found the issue.
 
craze1cars said:
My main concern is he’s asking way too much of this service box. I’d advise if car is charging, unplug entire trailer. And anytime trailer is plugged in, don’t charge the car.
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The photo shows the green breaker as a 30A and the red breaker as a 20A. We don’t know what is upstream of the box in the photos. Perhaps a 50A breaker? If so, that would restrict he addition of another breaker and outlet.

In any case, the 30A breaker should not trip with an 18A load.
 
Landshark said:
1. he photo shows the green breaker as a 30A and the red breaker as a 20A. We don’t know what is upstream of the box in the photos. Perhaps a 50A breaker?


2. In any case, the 30A breaker should not trip with an 18.
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1. Maybe? 30 amp breaker upstream is the only answer if your earlier speculation of 3600 watt service is correct. But maybe that’s just at the plug, not the box? I admit knowing nothing about RV park power distribution. But a 50 amp breaker for a single box would provide 6,000 watt service to the box...

2. Agreed. Something is wrong.

I still have more questions than answers...and more critical info keeps trickling out. Now we know that TWO residences are running off of this little box? Holy crap...
 
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The photos tell a lot. There is 120V available in the box, through one 30A green breaker and one 20A red breaker. The 30A breaker is connected to the 30A NEMA TT-30R outlet on the left that powers your trailer that is plugged in. On the right is a 20A duplex outlet that has had the connecting tabs removed so there are 2 hot wires and 2 neutral wires to that outlet (incidentally resulting in a code violation of 2 hots to 1 breaker). I see no ground wires, so I assume everything is grounded through the equipment ground to the box. The other person using the box on the 20A breaker has something plugged into both of the duplex receptacles on the outlet.

I assume from all this that the Clarity is plugged into a 120V outlet on the outside of the trailer, using the Honda EVSE cord. As long as the trailer is drawing less than 24A continuous (80% of the rated 30A circuit capacity) and there are no heavy load spikes, the breaker should stay on.
 
Sandroad said:
The photos tell a lot.
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You are absolutely correct. At this point I dot even plug the clarity on my side of the box, just occasionally stealing some juice from my neighbours outlet when he is not here (on the 20a side) - until I solve the mystery of 30a breaker.
I put a remote thermometer in the box and run my typical 18a load (a/c plus fridge plus lights, no car) - with open box it is 30 Celsius inside it, with front cover closed it is 35. No tripping yet.
But today is not the hottest day yet, will see on Saturday.
Meantime checked a hardware store if they have Stab-lok rated for more than 40 Celsius. Unfortunately not.
 
If I’m following along correctly, here’s what we know:

1) There is 120V power to the breaker box on the pedestal.
2) Breaker box contains 1, 30A breaker which powers a 30A outlet for RV power and a 20A breaker which powers a duplex outlet.
3) The 30A breaker trips frequently at ~18A.
4) The 20A breaker does not trip when charging a Clarity, 12A, or when powering the neighbors RV.
5) The wiring in the box is “unusual”.

What we don’t know is:

1) The source of the incoming power, the rating on the breaker protecting that circuit or what else that circuit may be powering.
2) Where the Clarity is plugged in when charging from the 30A source.
3) Anything about the wiring in the RV.
4) The maximum load on the 20A outlet from the neighbor’s RV.
5) Probably some other things, as well.

Some speculation. If the 30A trips at 18A, due to +40C temps, the 20A should trip at 12A, under the same conditions. Yet, it doesn’t when charging the Clarity or when the neighbor is plugged in. If there is a point to that potentially flawed speculation, and I’m not certain there is, it would be that the problem lies somewhere other that high ambient temperatures.

Typically, the power provided on a pedestal at an RV park is intended for one RV, unless there is a separate breaker box in the opposite side. The box will usually have a number that corresponds to the RV space number. The duplex outlet is generally considered to be a courtesy outlet for such things as a stand alone battery charger, a vacuum cleaner or an air compressor.

The attached photos show some bastardized wiring. I suspect that the problem lies in the wiring in the box or your RV and that you’re chasing your tail with the temperature theory.
 
I tend to agree that the temperature may be a lark. Having more trouble when it is hot outside is also consistent with a greater demand from the A/C in the RV, so hence a greater average current.

If it were me, I would be inclined to replace the 30A breaker with an identical replacement (because it is unlikely you will find a high temperature one). Replacement of the breaker is a trivial process, and could quite likely solve the problem. In any case, I think it is clear that you can't run both the RV's AC and the Clarity charger on this 30A breaker because that is at least 18A + 12A > 30A. You need to stay below 80% of the rating (24A in this case).

Of course, the usual caveat about being certain of your capabilities if you do this without the requisite electrician, etc...
 
craze1cars said:
1. Maybe? 30 amp breaker upstream is the only answer if your earlier speculation of 3600 watt service is correct. But maybe that’s just at the plug, not the box? I admit knowing nothing about RV park power distribution. But a 50 amp breaker for a single box would provide 6,000 watt service to the box...
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A 30A breaker upstream would be inappropriate. The box in the photos contains a 30A and a 20A.

The 3600 watt service is not speculation, it is the wattage available from a 30A outlet at 120V. As you’ve suggested, probably a 50A upstream.

FWIW: A 50A RV service is actually 2, 50A 120V legs which provides a maximum of 12,000 watts.

That RV park looks like an electrical disaster waiting to happen and is why I installed a 50A surge guard on my coach.
 
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What we don’t know is:

1) The source of the incoming power, the rating on the breaker protecting that circuit or what else that circuit may be powering.

Unknown. I would suspect could be another site or two.

2) Where the Clarity is plugged in when charging from the 30A source.

I do not charge the car on 30a now until the issue is resolved. A/c is more important to me now.

3) Anything about the wiring in the RV.

RV is almost new. Just opened the electrical box, one main 30a, several 15a and one 20a (for a/c) breakers. Measured the current on the main one, it matches perfectly the current in the pedestal box 30a circuit. Never trips. So I'd conclude RV itself is not an issue here.

4) The maximum load on the 20A outlet from the neighbor’s RV.

When neighbor is not here, his connector takes about 1.5 a, when I add my car - becomes 12.5 a.

5) Probably some other things, as well.

Will try to find thermal imaging camera and see if the breaker itself or any connector gets overheated. Meantime will have to suffer and try to survive in that hot Canadian climate
 
Interesting. You were paying for a 30A spot, yet your power was being throttled by a 20A breaker. I, for one, would not be a happy camper with that arrangement.

Now, management has installed a, presumably new, 30A breaker that regularly trips at 18A.

There is still an issue that needs to be addressed.
 
Alex800st said:
My RV does not have any batteries, it has 110 to 12 v inverter for lights etc.
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Alex800st said:
RV is almost new. Just opened the electrical box, one main 30a, several 15a and one 20a (for a/c) breakers. Measured the current on the main one, it matches perfectly the current in the pedestal box 30a circuit. Never trips. So I'd conclude RV itself is not an issue here.
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Are you certain there is not a 12V battery in the RV? The 120V to 12V converter typically acts as a charger as well. A battery would provide 12V power to the RV refrigerator (propane/electric) when 120V is unavailable and it is operating on propane. Assuming that you have such a refrigerator. These refrigerators also consume more electricity than a residential unit when operating on AC power. It is probably drawing 2-3A, the converter could draw 2-6A depending on its capacity and load demand.

I’ll assume that you have a travel trailer, in the 20’-24’ range, as opposed to a 5th wheel, given that you have a single roof AC and a 30A cable. The AC, either 13.5K or 15K BTU’s, will draw ~14A. The electric element in the water heater will draw ~12A.

The ~18A measurement you have observed, is, most likely, the load from the AC along with the refrigerator and converter/charger, and perhaps a phone charger or TV.

I may have missed it, but I do not believe you have informed us as to whether or not you have observed the load at the moment the breaker tripped.

It is possible that the water heater element is coming on, and it will stay on until the water is hot or the breaker trips, and adding ~12A to an existing load of ~18A. If this is the case, a simple solution would be to turn off the AC when hot water is needed and turn off the heating element when AC is needed. Alternatively, you could switch the heating element off and use propane exclusively to heat the water.
 
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Yes, absolutely no batteries. RV is permanently parked with water, septic and hydro (canadian name for power, no idea why, they are so weird sometimes) connected to it.
Water heater electric line disconnected from the panel (some bumhole (most likely me) used it on empty tank and burned the element, so it is gas only now).
I measure a load either in the box or on the main breaker inside the RV, and watch it - to be sure no sudden spikes from something I am not aware of.
I was looking around for infrared camera to check for hot spots inside the pedestal box - no luck. So I just tightened all connectors there - it definitely helped, now I can load up to 24A instead of 18A. So temperature is a factor no doubt.
I was looking for a stab-lok breaker rated for more than 40 Celcius - can't find it anywhere.
Will ask the owner if he will allow me to install third breaker - dedicated for the car.

Thanks a lot to DucRider and his idea - "I think there could be connection issue(s) within the box itself, and an electrician will likely be needed to sort it out. Poor connections will generate heat and could cause a breaker to trip, and from the looks of the box, it is not weather tight and corrosion could be a factor."

Some article with intersting graps I found - https://ieeexplore.ieee.org/stamp/stamp.jsp?arnumber=8669748

Looks like I will be able to survive next couple days here with temp reaching 31C.
 
Temperature is a factor. However, the study demonstrates that at a temperature of 45-50 Celsius (~120F) none of the 30A breakers tripped below 30A. They all tripped in a range from ~32-36A.

Figure 7 shows a 30A breaker will trip at 25A at 125C (~250F).

Prior to adding a 3rd breaker, the capacity of the breaker protecting the box at your site and any other sites on the same circuit needs to be determined.

Also, be sure to check the anode in the water heater and replace if necessary.
 
DucRider said:
I think there could be connection issue(s) within the box itself, and an electrician will likely be needed to sort it out. Poor connections will generate heat and could cause a breaker to trip, and from the looks of the box, it is not weather tight and corrosion could be a factor. They'll probably also correct code violations like the double tap on the red handled breaker.

The Stab Lok breakers (and panels) are also problematic, but usually the issue is failure to trip.
https://www.redbudinspections.com/dangers-of-stab-lok-circuit-breakers/
https://blog.societyinsurance.com/why-you-should-replace-federal-pacific-stab-lok-panels/
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Yes federal breakers have the distinction of holding more than rated load- and have been a favorite for welder installations over the years.
 
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