50 to 30am Electrical

[rrandall]

We have a 50 amp trailer that we use a dog bone to go down to 30 amp quite often. The last 2 times we did this, the male 30 amp got hot and shows melting where it plugs into the 30 amp service.  We only use one A/C unit when doing this.  Any thoughts?

 

[Seilerbird]

Either the dog bone is defective or the two outlets you plugged into are defective.

 

[rrandall]

Two different sites (same park) and two different dog bones.

 

[triplethreat]

A hot connection could be several things, but the first that comes to mind is a loose connection somewhere.  Did this only happen the last two time and was this at the same campground or different locations?  Campground low voltage will also cause a higher current.....but, the 30A breaker "should" trip if the current gets over the rated capacity of the breaker.  As far as connections go, those campground services get plugged into hundreds of times a year, and as a result, over time the recept. can get loose fitting.  Did your plug feel like it went into the recept. with some effort or did it just kind of slide right in and not much resistance to plugging it in?  That would/could be one source of a loose connection.  Other sources could be anywhere along the line/cord and all the way to where the incoming power lands on the main breaker in your trailers power panel and breaker box.

 

[rrandall]

Can't really remember about the way it went in.  It wasn't too hard to put in either time. The first time it was REALLY hot outside and that A/C had to work it's butt off.  The second time we were under more shade but it was still pretty warm outside. These are the only two times I've noticed any issues. I was thinking that we just had been pulling a lot of juice during the heat.

 

[Seilerbird]

Two different sites (same park) and two different dog bones.

Then it would be the outlets you are plugging into. 30 amp outlets can get worn from use over the years, even two of them.

 

[John From Detroit]

THey do that.  Make sure the blades on the dog bone are bright and shiny not dark and tarnished.

 

[Gary RV_Wizard]

Could also be a damaged wire in your 50A plug, either the neutral pin/wire or one of the hots.  Anything that interferes with current flow is going to cause heat when under a heavy amp load.

However, be aware that pulling 25-30 amps non-stop through a 30A outlet and the dogbone IS going to cause it to heat up.  At near-max amps, the temperature will rise, especially on a hot day (which of course is why you were drawing so many amps to begin with).