Really dumb extension cord Q

mowermech wrote:
This discussion triggered my curiosity, so I went outside and looked at my 30 amp RV extension cord. It is at least 50 feet long, perhaps 75.
Sure enough, it is 10/3 cable, rated specifically for 30 amp RV service. That information is stamped on the outer insulation.
I frequently run both air conditioners with that cord, no problem.
The 25 foot cable that is attached to the coach is also 10/3 cable, rated for 30 amp RV service.
So, if the OP installs a 30 amp socket and plug on his 10/3 cable, he should be in good shape, based on my ongoing experience with just such a commercial extension cord.

It may or may not be OK. You might have just had a combination of variables that worked.

When you run 2 air/con units, do you check for head build up? It may be slowly cooking the insulation and eventually you will have issues.

Also if the prongs are clean and shiny, they may be good but as they age and corrode, you may run into issues.

Finally, if you do this at a park that has good strong power, it may actually be getting 125v power. Go to a park with marginal power on a hot busy weekend where the voltage drops to 108v and your amperage will go up to compensate (watts = volts * amps). This may push you over the edge to where you start running into problems.

Ideally, you want to run the shortest cord that will reach (obviously, you can't change the length of the hard wired cord on a per trip basis).