Power cord connections melting

dougrainer wrote:

pianotuna wrote:
Thumbs,

For 50 amps the continuous rating is only 40 (on each leg)

For 30 amps the continous rating is 24 amps.

110 is safe--but low, assuming that is voltage under load. Consider getting an autoformer to correct the voltage.

Mine is set to boost voltage to 124. It cuts in at about 115 volts. No more burned plugs.

I have seen you quote this before. I have 43 years as a RV tech, the FIRST almost 24 years when everything was 30 amp and NO 50 amp RV's. I don't know where you get your mis info. RV electrical systems have their OWN national electrical rating and at no time in my 43 years have I ever hear of the 24 amps for 30 and the 40 amps for 50 amp service. Please post the reference for what you state. RV 30 amp is designed up to 30 amps(3600 watts) of service. 50 amp is for 100 amps(12000 watts). NO DERATING at all. Doug

I used to work with a group of Master Electricians. We got onto the subject one day and they were all unanimous that 30amps is the peak load and continuous would be 80%.

I don't have a copy of the code book handy but I know people who push the limits and they tend to get burnt up plugs.

Maybe they were wrong and you are right but I'll take the option that doesn't burn up my plugs.

To the OP:

It might simply be a loose or corroded connection creating the heat.

Were you able to put an amp-meter on to see what it is actually pulling. You mentioned no hot water heater or microwave but what about other loads like the battery charger. If voltage is low amperage on motors will be higher (110v is in spec but towards the low end). The air/con might be pulling 15amps with low voltage. The battery charger might be pulling another 7-9amps depending on the size. A few misc items (tv, phone charges, etc...) and you might be bumping up against 30amps for longer durations. Now you are taking what are often marginal installations and pushing them till something fails.

How were you verifying the voltage? Put a meter on the plug and see 110v and when you apply a big load like the air/con, voltage may be drug down a few volts. Also, it will likely change based on conditions. Early morning when it's still cool, the voltage is often strong but on a hot day, mid afternoon, it's not uncommon for voltage to drop 8-10v...or more if the park system is marginal.

It also may be a combination effect. A marginal connection between plug & outlet might not be an issue when puling 3-4amps but when pushing to the limits, it can be.