30 amp rv extension cord 100 ft

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100 ft. 30 amp 10 gauge extension cord

100 ft. 30 amp 10 gauge extension cord max 600 Volts 30 AMP overload. RV 30 amp extension cord, Max Rate 7500 Watt (125 Voltage)

I see this on Amazon with 5 star ratings--everyone with a 30 amp camper seems pleased. I didn't think 10 gauge would work with 100 ft. extension.

I have a 50 amp Winnebago Voyage motorhome that also will run on 30 amps. It has a Power Management System. Do you think this would somehow work? You can tell I am surprised. I was lookin for a 6 gauge wire !!!!

EDITED: just got this " if you are purchasing the 100 foot model the Amps will de-rate to 25 Amps, or 6,250 Watts."

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Not sure where your getting the watt rating but 30 amps at 120 volt is 3600 watts.

Although your 50 amp RV is wired for 240 volts, that's not what a 30 amp cord is carrying. If its derating to 25 amps, your down to 3000 watts shared between two 120 volt legs.

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Join Date: Feb 2017

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Will it work? Sure, but ...

Voltage drop increases as wire size decreases, wire length increases and current increases.

In your scenario - 100ft of 10awg cable at 30 amps will result in a loss of about 6 volts. So if you plugged in to 120 volts your rv will get 114 volts. This is about double what is recommended. The voltage loss is mostly linear so to be on the "safe" side, 15 amps would be about the most you should run on this cord.

Higher voltage drops will result in hotter cables and could damage sensitive electrical equipment.

Another problem is that many rv sites don't provide a full 120 volts to begin with so your actual voltage at the rv will be even lower.

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Jack
2007 Winnebago Sightseer 35J
2003 Ford Sport Trac

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100 ' #10 would work fine BUT buy 2 30 amp plugs.Cut the cord in 1/2. Not often you would need 100 Feet. 100' of #10 is tuff to deal with.Been there done that.

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A 100 foot cord would hardly ever be needed with routine RVing so I'm taking it the OP wants the cord to be used at home or at another location. Would be fine if the idea is to power the convertor/charger to keep batteries maintained. I'd still check for voltage drop and heating of connections if I tried it.

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Quick lesson in extension cords. (I believe the industry calls them "service cords" or simply "cordage".)

Unlike house wiring (Romex) extension cords use stranded wire for flexibility. Also Romex (a brand name owned by Southwire; industry term is NM-B or UF-B for direct burial cable) only counts the conductors that carry current. 12/2 has 2 conductors plus ground. Extension cord wire COUNT ALL CONDUCTORS !

The most common cord are rated either SOOW or SJOOW.
S= Service
J = Junior (max 300V) (no letter means 600V rating)
OO = Outer and inner insulators are rated for use in oily environments
W = Weather/water resistant
T = Thermoplastic insulation; lighter and cheaper but stiffer (VERY stiff in cold weather)

SOOW are heavier and more expensive than SJOOW. They should handle rough use better, but coiling 50' of SOOW is a chore !

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Use this wire size calculator to see what wire size you should use( #6) for a 30A 100' cable. A 3% voltage drop is the acceptable safe standard.

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I bought a 25' extension cord from Walmart and had problems with the plug burning on it. Cut it off and when I went to strip the wires found the 10ga holes in my strippers were too large, had to drop down to the 12ga holes. Chinese junk.
I finally went to Lowe's and bought 50' of Southwire 10/3 600 volt wire and installed it on my coach. This way I don't have to use and extension cord.
Voltage drop with one Coleman Mach Power Saver a/c is about 1 volt. Still have 120 vac at my coach when plugged in at home or my SIL's place.

I would not buy a made in Chinese cord as an extension.

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Quote:

Originally Posted by leadman

I bought a 25' extension cord from Walmart and had problems with the plug burning on it. Cut it off and when I went to strip the wires found the 10ga holes in my strippers were too large, had to drop down to the 12ga holes. Chinese junk.
I finally went to Lowe's and bought 50' of Southwire 10/3 600 volt wire and installed it on my coach. This way I don't have to use and extension cord.

You can find Southwire or Carol SJOOW 10/3 on eBay for a lot less than at Lowes or Home Depot. (Stick with SJOOW. The 600V rating of SOOW is not necessary.)

UL approved male and female ends (NEMA TT-30P and NEMA TT-30P) are much cheaper on eBay.

I hope you turn that piece of cable you removed from your RV into an extension cord !

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theoldwizard, I was camping in my SILs driveway last year when the plug on the extension cord decided to burn. Had to fix it immediately so Lowe's was close by. The guy gave me a break on the cord, was about $90. I did fix the old cord from the motorhome so it is now and extension.
The Walmart cord got repurposed for use in my boat.