30 amp plug hot and started to melt

If you don't turn the power off before plugging in, the converter/charge has a momentary inrush current that causes pitting and dirt buildup leading to a bad connection. Same thing happens inside a CG pedestal from the many RV-ers that don't turn the power off first. A CG recept. can become loose due to physical abuse they get and age, and in some cases can be corroded inside if in a wet, high humidity environment. The result is a connection with high resistance that can overheat and melt and even go up in smoke & flames.

Drawing more current from the pedestal will increase the chances of a meltdown. Low voltage causes an AC unit to draw more current. Having a permanent plug-in or hardwired digital voltmeter is a good idea and an EMS is the best thing to have to protect you against low voltage.

If you are at a site and the recept. in the pedestal looks crispy, blackened and in rough shape and/or the plug wants to fall out of the recept., consider finding another site. If you can't and the whole CG is bad (BTDT), don't run the AC and keep loads to a minimum. If the voltage is really low, like near 105 volts, an autoformer can help in these situations. If the voltage gets below 105 volts, turn the AC unit off. For situations when the pedestal recept. is in bad shape and you have no other choice, you could use a 30 amp to 30 amp pigtail adapter so that only the adapter will get damaged- Camco has one and we carry one just in case.

Always turn power off before plugging in and always make sure your shore power plug blades are kept clean with some emery cloth or sandpaper as needed. If you see a pedestal like in the photo, expect trouble before you even plug into it and go elsewhere if you can. This one needed a stick to hold the plug in place.

MEXICOWANDERER wrote:
Is there enough room in the plug tp accept 8-gauge x #8 spade terminals? This stops the strand unfurlimg problem forever. I adopted these terminals 40 years ago. Then I could purchase whatever plug or receptacle. A zot of spray undercoating covering it protects for years. Same with gooshing some dielectric grease through slots or onto plug blades.

But all that won't do a danged thing for a bad park recrptacle :(

Dielectric grease does not improve conductivity. It is used to prevent corrosion. It won't improve the condition of the contacts and actually has insulating properties, so it may actually degrade the connection. "Gooshing" it into the slots of the park's receptacles will just make them greasy.

Is there enough room in the plug tp accept 8-gauge x #8 spade terminals? This stops the strand unfurlimg problem forever. I adopted these terminals 40 years ago. Then I could purchase whatever plug or receptacle. A zot of spray undercoating covering it protects for years. Same with gooshing some dielectric grease through slots or onto plug blades.

But all that won't do a danged thing for a bad park recrptacle :(

For replacement, I very highly recommend the Progressive Industries connector- most, if not all of the others make you twist the stranded wire and try to make it stay under a screw. With the P.I. model the stranded wire is captive- stick it in and tighten up the screw. It also has a round ground, rather than U shaped.

Damage can be prevented by checking for warmth when drawing a high load. Similarly checking hose bib for leaks. I do two checks:

15-minutes after I start high load

Then an hour after that

I have seen several 30 amp plugs melt.. and one 50.. just one 50. They melt.

Just replace it and have fun.

Moved from Roads and Routes to Tech Issues

western park has it right........IBEW 40 years.........

If the heat damage is to the face of the plug and the blade area, the problem is likely bad contact within the pedestal. That can be caused by a worn receptacle or the blades of the plug having a lot of corrosion (they look black instead of bright golden bronze). Solution, polish the blades with an emery cloth if it's the blades and have the park replace the receptacle if that is the problem.
If the damage is closer to the cord, the problem is the wiring has come loose within the plug or the wire is damaged due to flexing the cord. Solution to that is cut the plug off and replace with a new one (simple for all but the completely mechanically inept, though it does require some ability to apply force).

fla-gypsy wrote:
The receptacle is bad or the park system was overloaded causing low voltage which is hard on plugs and RV systems

Low voltage itself is not hard on plugs. High currents are hard on plugs, and some devices (most notably air conditioners starting up) draw more current for longer when the voltage is low. However, even then the circuit breaker should trip before current enough to cause plug damage flows provided the connection to the socket is solid.

The worn receptacle (or poor connection to its wire) caused a high resistance connection, which caused power to be dissipated in the socket or the plug connection and hence the heating.