U-Haul VT16 Blown 110v

[Jonathan Wright]

Ruh-roh.

I got caught in a bad spring storm in the Colorado high country in my U-Haul VT16, and was running an electrical space heater along with a small 110v bar refrigerator while plugged into 110v shore power. I then started a small microwave, and it blew the breakers.

Flipping the main breakers is not fixing the problem, and the small push button resets on the 110v outlets wont stay in either. Shore power is working from a small building which I have had to connect to with a 50ft 12ga extension.

Anyone have input on starting points in process of elimination to troubleshoot? I realize this is pretty general, and that I'm not electrically competent. Thank you!

Jonathan

[Dennis Clinton]

I don't have my chart with me, but here's some things to consider:
1. 12 ga wire will handle 20 amps, but voltage drops over length.
2. Your space heater probably uses 15amps.
3. Refrigerator uses 1-3 amps
4. Microwave can use 5 or more amps.
So your total usage is mosty likely over the capacity of the extension cord and breakers(you did not say what the breaker capacity was).
First-test the cord to make sure it didn't overheat and short. Then try one appliance at a time. Is the reset button on the outlet a breaker or GFI?. If it's a GFI, you have something wrong downstream from the plug.
Hope this helps.

[Jonathan Wright]

Dennis --

The cord is working, and running the space heater with the cord out the door. There are some previously un-noticed mouse nibbles on it, but nothing that apparently compromised it. The main breakers are heavy flip switches, and it appears that the resets on the 110v outlets are GFCI's -- small push buttons under the socket elements.

If there is something wrong inbetween the GFCI and the main breaker, would the next step be to pull the 110v outlets and check for continuity? What are the chances that either the Breakers or CFCI need replacement? Thanks for your time here.

[Dennis Clinton]

Are they the original 1985 breakers? Breakers do get old and 'pop' at a lower amperage after a while. Are the breakers still popping off? If not, I would follow the wiring from the breakers to the individual outlets. You stated the GFI's are still popping when you plug something in. If so, then the problem is with what you are plugging in. Try plugging something simple in, like just a light that you know is good. If the GFI still pops, you may need to replace the outlet.

[Timber Wolf]

If all the GFCI's (and they are GFCI) are acting the same I would suspect a Neutral (also known as the "grounded conductor") bus bar issue. You may have had a significant event that blew breakers, which are now able to reset but it also caused a problem with your Neutral wiring that resetting the breakers does not address. Look over the Neutral bus bar in the panel for signs (scorching) of a problem. Maybe a small break somewhere in the shorepower cord Neutral side too.

[luvrOlife]

Hi Jonathan,

In case you weren't aware, there is a very active UHaul Campers group on FB that have knowledgeable users for this issue. You may want to post this there also.

[Kevin A]

Nothing worked for us on a trip a few years ago following a storm. We were using the microwave and AC at the time. I ended up putting new circuit breakers in the breaker box under the front table on the VT and everything worked again. Apparently the old breakers were shot. I've also had two GFCI outlets go bad, needing replacement. You might want to start by replacing the main, and test from there.

[Joe MacDonald]

check all your outlets, if you have power from the shore outlet, one of your GFI's could be tripped, sometimes the gfi's are fed in series( ok by design) if any one of them trips, the rest of the plugs after the one that tripped won't work. this could be a plug for a fridge or water heater you don't normally use.

Joe

[Jonathan Wright]

Thanks for all the responses! I have now replaced the GFI outlets and one of the main breakers, which I discovered to be a 30 Amp. There was a disconnected 20 amp breaker next to it in the box. This is disconcerting, and strikes me as creative engineering on the part of the previous owner. I still have no 110 power to outlets, but the 12v lighting is working off the battery.

I just had a friend who has a degree in electrical engineering stop by to discuss, and he said the next step is to start checking continuity, as he feels the 30 amp breaker may have allowed hard wiring in the walls to have fried if the system is engineered to be 20 amp. There may be a need to rewire the outlets from the breakers to the first outlets that were involved when everything blew.

[steve dunham]

Originally Posted by Jonathan Wright

Thanks for all the responses! I have now replaced the GFI outlets and one of the main breakers, which I discovered to be a 30 Amp. There was a disconnected 20 amp breaker next to it in the box. This is disconcerting, and strikes me as creative engineering on the part of the previous owner. I still have no 110 power to outlets, but the 12v lighting is working off the battery.

I just had a friend who has a degree in electrical engineering stop by to discuss, and he said the next step is to start checking continuity, as he feels the 30 amp breaker may have allowed hard wiring in the walls to have fried if the system is engineered to be 20 amp. There may be a need to rewire the outlets from the breakers to the first outlets that were involved when everything blew.

I seriously doubt you burned up a wire in the wall . In a night school experiment for my night school students ,we replaced the fuse link in a renewable link fuse with a piece of # 12 solid copper wire , The apprentices had to guess how many amps it would take to melt the # 12 conductor and open the fuse . It took "168 AMPS" to open the fuse , far more current than 30 amps . If the 30 amp single pole breaker in your breaker panel can be reset and you have power at the breaker's load terminals , the problem is in or at the GFCI ,or downstream from the GFCI or a neutral problem or the neutral and the grounding conductor are unintentionally connected or ???? Plus if you look in Art 310-16 of the NEC you will see that a 90C # 12 copper conductor (Romex cable contains 90C conductors) has a listed ampacity of 30 Amps but is limited to over current protection of 20 amps by a FPN. If a wires does burn off it is usually due to a poor splice or an improper , loose or rusted termination