A question on rolled shore power cords

The basis for many electrical capacity determinations is the ability of the item to shed heat resulting from current flow. As the temperature of a wire increases, so does it's resistance and associated voltage drop. A long, coiled, light gauge electrical extension cord carrying a greater load than it is rated for can get hot enough to melt the insulation. Most trailer cords do not seem to reach this condition being properly sized for their load.
If you want warning for this particular event I would suggest you get a plug-in voltage monitor with an alarm function.

Check your cord after a long run with the generator and A/C's in use. If it's not noticeably warm there's nothing to worry about.

Raist11 wrote:
Good morning all,

So I've read many stories and posts about the dangers of having your shore power cord rolled up when plugged in. I've even heard that a regular extension cord rolled up when in use can be a fire hazard.

My question is this.. My 1990 Triple E has a female plug in the compartment for my shore cord for when I use my generator. Wwhen on the road, obviously I can't leave the cord run out underneath the motorhome. It has to be nicely rolled up in it's compartment. And that thing gets hot after a day of travel on a warm day. Is this just the way those with this setup just have to do it? It makes me nervous every time we're traveling. Fortunately our travels don't take us very far.

Thanks for any insight.

I know exactly what you are talking about, driving through the desert southwest after stopping to fill up, I checked the gen set as well, cable was really hot, looking to hear more from others

You should be fine as long as you don't cover the coiled cord with anything; especially anything padded like a tablecloth or blanket, tarp, etc. That would allow heat to build up rapidly and might cause problems. Otherwise, there should be adequate ventilation to keep it below dangerous temps. The rubber and/or plastic insulation's ignition temperatures are on the low side around 250 degrees F and on the high side of around 500 degrees F. If it gets that hot just coiled up while plugged into the generator, you've got a lot more problems....like something drawing a HUGE amount of amperage. As a general practice, I keep my cord in a figure 8 pattern in the bin when traveling...it's just easier to deploy when I get where I'm going. Harder to pack, but easier to deploy. I don't have plug it into anything when on generator, but I can see how a figure-8 coil would allow better ventilation in your situation rather than just a straight coil.

Thanks for the quick responses. I will say, it gets hot but I don't think 500F HOT though. Perhaps I need to limit items that are running on it, a couple I can think of off the top of my head. We use a small powered cooler, I can run that off the chassis in a cigarette lighter instead though. Not that I feel it will make a big difference, just thinking cutting out whatever I can.

The compartment is rather small, definitely not large enough for a figure 8 pattern. I do ensure it is a nice roll and never jammed up in there. I'd like to think the RV builder knew that this would be adequate.. but when I look at the lack of access to my brake fluid reservoir... I'm not so confident.

I don't think it is much of an issue otherwise there would be a lot of flaming RVs in the campgrounds. Most shore power cord compartments are small in order to save interior space. I see a lot of campers just pull out the minimum length of cord needed to make the plug-in at the pedestal, the rest is left coiled in the compartment.

However, I am not familiar with running generators hooked to power cords while on the road and cannot comment on that situation.

3oaks wrote:
I don't think it is much of an issue otherwise there would be a lot of flaming RVs in the campgrounds. Most shore power cord compartments are small in order to save interior space. I see a lot of campers just pull out the minimum length of cord needed to make the plug-in at the pedestal, the rest is left coiled in the compartment.

However, I am not familiar with running generators hooked to power cords while on the road and cannot comment on that situation.

Well, there have been flaming RVs in campgrounds due to the shore power cord being coiled up. I have even seen reports of it happening at home, a garage burnt down due to the heater cord being coiled up and igniting. Now of course it isn't a "common" thing. I have left extension cords coiled up all my life without issue. But this is a new arena for me, so after hearing these reports and stories I started to wonder.

I leave most of my 50amp cable rolled up in my electrical basement compartment. I only take out enough to reach the power pedestal. Been doing this since 1974.

Cite a reference stating a coiled cord is a fire hazard. "I heard" is not a valid reference.

I solved the issue by cutting off the cord. I added a male end to the cut off RV cord, and a female end to the remainder.

Generally the generator is not able to deliver full power to the RV For example my Generator is only 5500 watts. the max possible shore draw is 1200 watts.

However even that. If you must coil.. Make the coil as LARGE as possible. The larger the coil the cooler the coil

I once had a 100' coil of 12ga.. Layed out this could pass 20 amps packed in a wall.. MORE lying in open air.. Coiled I was pulling no more than 10 and that puppy got hot, Not dangerously hot, but hotter than I was comfortable with.

That is why I caution against it.. But if a large coil should be ok. The fewer turns in teh coil the better.