wa8yxm
Wherever I happen to park
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Kirk wrote:There is some truth to several of the answers, but in my experience in 40 years of electrical service I have also learned that every time you add another plug into a circuit that draws significant loads, you will introduce heat. Poor connections or corroded contacts will cause heat but even clean, bright contacts that fit tight will heat up if there is a heavy load.
Good info Kirk, However re-read the Original Post please
I believe he spoke of the junction Between the extension cord and his rig's cord.
Thus he had only one cord plugged in there
had it been the first cord plugged into the park box.. I'd agree with you
In his case. it is also possible that due to the autoformer he was drawing a bit more current (since all those rigs were drawing down the voltage a bit) but in this case he should not have gotten melted plug/outlets.. he should have gotten the CLICK of darkness as the circuit breaker did it's job.
On edit.. I re-read the Original Post to verify HE did speak of the Extension-Primary rig cord, junction.
Nothin adds excitment like something that is none of your business
John is Near Kenwood TS-2000 housed in a 2005 Damon Intruder 377
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Ray,IN
IN, USA
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Kirk wrote:There is some truth to several of the answers, but in my experience in 40 years of electrical service I have also learned that every time you add another plug into a circuit that draws significant loads, you will introduce heat. Poor connections or corroded contacts will cause heat but even clean, bright contacts that fit tight will heat up if there is a heavy load.
If you have ever purchased an electric heater or other such appliance and read the warnings, it always warns against the use of extension cords. The reason is that when you load any power cord to near it's max rated load it will get hot. The higher the load the greater the heat. If you consult the wire size charts, you will discover that the longer the run of electric cable, the larger the required wire diameter for the same current. Voltage drop is the reason and heat is what happens to that lost voltage.
It would be my guess that you were operating the air conditioners for long periods of time and that load is what melted the cords. This it not at all unusual.
When this man speaks, LISTEN! Kirk is an expert electrician; and, he's been living in his RV for years full-timing.
To the OP, did you both monitor line voltage in your RV? 108 VAC is the safe minimum, below that you are damaging some stuff.
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wa8yxm
Wherever I happen to park
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Oh, I do agree his answer was good Ray.. (And said as much) I've been doing electronics for 40 years as well.. Cross trained in electrical (Which only occasionally causes issues cause everyone knows the Ground lead is BLACK right?
Answer: NOT if you are an electrician. They use Green (or bare) and the black lead is as far from ground as you can get (HOT)
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rvten
Crossville,TN
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Low voltage will make for high amp draw. Makes everything get hot. I have melted one because of this. Use a surge guard and keep an eye on the volt meter.
Tom & Bonnie
Crossville, TN.
Aspect 29H 2008
Class C passed Class A owner
Pontiac G6
There is NO such Thing as a B+
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wa8yxm
Wherever I happen to park
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I agree with you Tom (or is it Bonnie) low voltage will increase amp draw on a A/C motor.. However.. the man has 30 amp cords and it's a 30 amp breaker so if the current was excessive per the cord rating.. CLICK of darkness should have ensued.
That said.. Just because the breaker says "30" upon it, don't mean it will trip at 31 (or 35) amps
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rvten
Crossville,TN
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Mine was the 30 amp cord off my MH(not this one).
We were plugged in to a big panel with everyone else. Old CG. Everyone trying to run ther A/C's. Power dropped into the red plug got soft and melted. This was before I invested in a surge protector.
I now carry extra male plugs.
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Retired Army SSG
Turner, Oregon
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rubadubtub one easy thing to remember is dont use an extension cord that is not rated for 30amps, that is what is mostly installed on RV's the larger RV's have a 50amp cord. If you just remember not to use smaller wire size that what your RV's elec cord is and you will be fine
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randco
Sarasota, Florida
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The longer the extension cord, the more resistance. More resistance means more heat.
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samuraitowd
Washoe Valley, NV, USA
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I just cooked an extension cord by running the roof ac continuously. Most extension cords are rated at 15 amps but I think that is for short bursts like a homeowner or contractor would use it for tools. I switched to a heavier duty (larger wires) ext cord from Home Depot and had no problems.
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Rick n Andy n SandyPaws
Rexhall American Clipper 29': 2005
Suzuki Samurai; 1994
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