Hooking up 30A at home

[eldel]

I'd really like to be able to run the AC on my rig when I've got it parked outside the house before we take off on a trip. The 110V house supply isn't enough but I do have a 220V / 30A outlet in the garage which is a 14-30 outlet.

I'm looking and reading but I don't see anywhere where I can get a 14-30 to TT-30 converter. 14-50 to TT-30 yes. Is this even possible (assuming that the 14-50 converter just splits 220/50 into 2 x 110/25) or am I looking at wiring in a new circuit?

[MEXICOWANDERER]

One faulty pole transformer can imply dangerous earth ground voltage potential between line to earth. Ask US Pumice, about their 278 volts line to earth ground potential. This started a war between Southern California Edison and the Mineworkers and US Government OSHA. The fault lie with the bank of ground transformers on SCE property nearby. No one took my advice and change the bank to additive rather than subtractive polarity units. They had to go to war. Court, lawyers. I do not know and I do not care about the outcome. My issue was solely with safety.

It takes a moment just a moment to verify line to earth ground potential. I ran into this again with the hotel down here. The pole transformer was shorted. 163 volts line 1 or 2 to earth ground and 91 volts line to neutral line 2. CFE ignored my compaint. Then the transformer caught fire.

[Hurricaner]

The code was changed in 96 requiring a 4 wire for dryers, but you better test that outlet because a table saw is straight 240 and does not need a neutral.

Sam

[Bobbo]

You have 3 good options.
1. use the above adapter to go from 14-30 to TT30
2. replace 14-30 with 14-50 and use standard RV adapter to TT30. It is good to own that adapter anyway.
3. replace 14-30 with TT30 and tape off the unused hot wire (at both ends)

Actually, you have a 4th option. Put a pedestal box there with 50/30/20 outlets. That gives you the most flexibility for future growth.

[wnjj]

eldel wrote:
OP here - just got chased out of Wyoming by the snow 🙂

Thanks for all the input. For clarity the previous RV (TT) AC would run happily from the 15A house circuit. The replacement (C class) AC trips the breaker in about 20 seconds. The 14-30 is not the dryer but a separate circuit that we put in to run a table saw. Which never happened but that's another story.

It looks like the easiest answer is to replace the 14-30 outlet with a 14-50 one. Failing that I'll buy an adapter from the ev place.

There's a direct adapter on Amazon I posted previously: https://www.amazon.com/AC-WORKS-Generator-Adapter-4-Prong/dp/B07WN9ZZ6W?th=1

I agree that swapping the receptacle is the easiest/cheapest way to get what you want, provided you no longer want the 14-30.

[pianotuna]

Bobbo wrote:
Since it is an unused circuit, putting in a 14-50 is the ideal solution. (The 14-30 to 14-50 adapter would never be used camping. All the campgrounds are already 14-50.)

LOL you must go to a better class of campground than I do!

[Bobbo]

Since it is an unused circuit, putting in a 14-50 is the ideal solution. (The 14-30 to 14-50 adapter would never be used camping. All the campgrounds are already 14-50.)

[enblethen]

That works good as you may need the adapter while on the road. They come in handy!

[eldel]

OP here - just got chased out of Wyoming by the snow 🙂

Thanks for all the input. For clarity the previous RV (TT) AC would run happily from the 15A house circuit. The replacement (C class) AC trips the breaker in about 20 seconds. The 14-30 is not the dryer but a separate circuit that we put in to run a table saw. Which never happened but that's another story.

It looks like the easiest answer is to replace the 14-30 outlet with a 14-50 one. Failing that I'll buy an adapter from the ev place.

[time2roll]

ktmrfs wrote:

enblethen wrote:
Ktmrfs: you do agree that dryers are 120/240 and not straight 220 volts AC?
Proper installation of a device is critical?

yes, Dryer outlet has two 120V legs, neutral and ground. In fact parts of the dryer typically run on 120V, like the motor and controller board. Usually only the heating element is 220V.

for years NEC code allowed dryers, ovens, cooktops outlets to share neutral and ground. No longer. Now they must be a 4 wire with seperate neutral and ground. If you buy a new dryer, cooktop, stove, etc. they now come with instructions on how to connect the ground for both systems, common ground/neutral and seperate ground/neutral

Regardless of history or the interworkings of a clothes dryer... OP said he had a NEMA 14-30 that he wanted to use.

[coolmom42]

Lynnmor wrote:
Such a simple circuit to run, I can't imagine all the discussion when a new wire can be run from the panel to a new outlet and have an excellent solution.

It's simple if 1) you have enough room in the breaker panel for a new 30 amp circuit and 2) the breaker panel is reasonably close to the new outlet location.

Luckily I have both, as I discovered after checking the breaker panel.

[ktmrfs]

enblethen wrote:
Ktmrfs: you do agree that dryers are 120/240 and not straight 220 volts AC?
Proper installation of a device is critical?

yes, Dryer outlet has two 120V legs, neutral and ground. In fact parts of the dryer typically run on 120V, like the motor and controller board. Usually only the heating element is 220V.

for years NEC code allowed dryers, ovens, cooktops outlets to share neutral and ground. No longer. Now they must be a 4 wire with seperate neutral and ground. If you buy a new dryer, cooktop, stove, etc. they now come with instructions on how to connect the ground for both systems, common ground/neutral and seperate ground/neutral

[enblethen]

Ktmrfs: you do agree that dryers are 120/240 and not straight 220 volts AC?
Proper installation of a device is critical?

[ktmrfs]

enblethen wrote:
Dryers are 120/240! NEC revised code numerous years ago to require four wire circuit. Early dryers used the ground as neutral.

there are likely a LARGE number of houses with the old 3 wire combined ground/neutral hookup. (dryer, range, cooktop etc.) That code didn't change till the late 80's or maybe even the 90's. And that is perfectly fine to keep using until you do a upgrade to the dedicated circuit.

[Bobbo]

time2roll wrote:

Bobbo wrote:

way2roll wrote:
Why do you say the house current isn't enough? I run a 50/30/15 adapter and plug it into an exterior house outlet. As long as I am careful to run one AC only, no problem. Seems like this is more complicated than it needs to be unless I am missing something.

House loads on that circuit. He not only has to count RV loads, he has to count house loads too.

Dryer circuit is virtually always a dedicated circuit.

True, about the circuit he WANTS to use. However, I am referencing the circuit he is CURRENTLY (pun pun) using, an outdoor 15 amp outlet.

way2roll wrote:
I get that, but there is usually one circuit - like the outside receptacles that are isolated to the same circuit. And of course you can always monitor what's on the circuit.

Which is exactly what he is trying to stop having to do.