need help with electrical questions

[Docv]

i am buying a 2019 classic 30 ft twin this year, i need to prepare a concrete slab and cover for it next to my cabin.
i want to get an electrical outlet there as well
do i need 240 volt for an 50 amp outlet or can i use 120?
the only thing i know about electricity is to flip a switch

[paiceman]

120-50amp. I had one put in by licensed electrician, despite being told several times he wired it up like an electric dryer. Plugged in, blew converter and blue ray. He paid for all

[Mollysdad]

Well, at the cabin end it's the same wiring for both.
At the RV end the two hots are not used as a pair, so you end up with (2) 120v. circuits.

Originally Posted by paiceman

120-50amp. I had one put in by licensed electrician, despite being told several times he wired it up like an electric dryer. Plugged in, blew converter and blue ray. He paid for all

I'm not a licensed electrician, but I can't understand what he did. A 240 v. dryer plug is not the same as a 120 v. RV plug.
So perhaps he took a RV female 30 amp plug and wired it as IF it were a 240 v. dryer plug with hot, hot, ground/neutral.
(In a dryer plug the ground is an angled spade, in the RV the ground is a pin.)

[Al and Missy]

A dryer receptacle has three contacts, the RV has four. RV 50A service is the same as 240V, just also has the neutral (white wire). Hot 1 - Black, Hot 2 - Red, Neutral - White, and Ground - Green. Airstreams only use the service as two separate 120V circuits, Hot 1 to Neutral and Hot 2 to neutral. Some RVs, particularly large Class A's with residential appliances like dryers and ranges use Hot 1 to Hot 2 which gives 240V. If you have the 4-contact receptacle wired correctly your Airstream will get two 120V 50A circuits just as intended.

Al

[chasrolex69]

HI, i have a 50 amp outlet that is in a metal weather proof outdoor box and very high end that i bought last year ,but decided not to have it installed. it is yours if you would like it, going to waste , new in the box approx $80 retail, just email me with your shipping info cmadison@napleton.com

Charles

[Docv]

Originally Posted by chasrolex69

HI, i have a 50 amp outlet that is in a metal weather proof outdoor box and very high end that i bought last year ,but decided not to have it installed. it is yours if you would like it, going to waste , new in the box approx $80 retail, just email me with your shipping info cmadison@napleton.com

Charles

i will take it
Erik van Ginkel 6281 coral lake drive miami fl 33155
thanks

[chasrolex69]

On its way to you first thing Monday morn. enjoy your Airstream!

[dasams]

Originally Posted by Docv

do i need 240 volt for an 50 amp outlet or can i use 120?

Just to clarify, an AS with 50 amp service has the ability to pull up to 100 amps. At the pedestal, the 50 amps are at 240 volts. The phases are separated in the four prong plug and pass through the cable in separate wires. Hence you'll have 2 x 50 amps. Look in your breaker panel and you'll see two 50 amp breakers.

You can install a 50 amp 120V plug and it'll function normally. Just be aware that you may trip the breaker if both AC's are running and you turn on the microwave while your wife is blow drying her hair

If you go the 120V route, you'll need a dogbone with a 50 amp three prong male to 50 amp four prong female. I've never seen one but the 30 amp > 50 amp dogbanes are common. See https://www.amazon.com/Camco-Dogbone...amp+rv+adapter

If your site is mainly for storage and can get by with 30 amps, then have your electrical install a 30 amp plug and use the 30 > 50 amp dogbone. But you can use only one AC at a time.

[Al and Missy]

Originally Posted by dasams

Just to clarify, an AS with 50 amp service has the ability to pull up to 100 amps. At the pedestal, the 50 amps are at 240 volts. The phases are separated in the four prong plug and pass through the Monster cable in separate wires. Hence you'll have 2 x 50 amps. Look in your breaker panel and you'll see two 50 am breakers.

You can install a 50 amp 120V plug and it'll function normally. Just be aware that you may trip the breaker if both AC's are running and you turn on the microwave while your wife is blow drying her hair

If you go the 120V route, you'll need a dogbone with a 50 amp three prong male to 50 amp four prong female. I've never seen one but the 30 amp > 50 amp are common. See https://www.amazon.com/Camco-Dogbone...amp+rv+adapter

From an Airstream's perspective, both 30 amp and 50 amp are 120 volts. If OP's trailer has 50A wiring, he should install a 50A service, but be sure that it is wired for an RV: 2 hot lines, one neutral, one ground - not a dryer hookup which doesn't have the neutral. "50A service" for RV's is really 100A service, i.e. 2 separate 50A 120V services. Only one neutral is required because the two 120V legs are 180 degrees out of phase. The neutral only carries the difference in the current between the two 120V hot wires.

If Op's trailer has 30A service, he could get by with a 30A service, but I'd still recommend he install 50A service for upgrade potential. The 50A 240V RV service will cost a little more than the 30A since it is larger wire and 4 wires instead of three, but it should be mostly material costs. The electrician doesn't do substantially more to run a 4-wire cable that he would do to run a 3-wire cable.

As to the dogbone, while OP might be able to find a 120V 50A connector, it is not going to be an RV style and there probably is not a dogbone to translate it to a 50 RV connector. Plus, 50 A at 120V only gives you a total of 50A, not 100 like the standard 50A service.

Bite the bullet and put in a 120/240 4-wire 50A service and you'll be good to go.

Al

[paiceman]

Originally Posted by Mollysdad

Well, at the cabin end it's the same wiring for both.
At the RV end the two hots are not used as a pair, so you end up with (2) 120v. circuits.

I'm not a licensed electrician, but I can't understand what he did. A 240 v. dryer plug is not the same as a 120 v. RV plug.
So perhaps he took a RV female 30 amp plug and wired it as IF it were a 240 v. dryer plug with hot, hot, ground/neutral.
(In a dryer plug the ground is an angled spade, in the RV the ground is a pin.)

That’s what he did

[james.mileur]

This is a good description.

[TG Twinkie]

Modern dryers have a 4 wire plug and receptacle.
L1, L2, Neutral, and ground
The only part of a dryer that uses 240 volts is the heating element. The control system and drum motor are 120 volt.
Older dryers with 3 prong plugs do have a neutral. It is tied in with the ground.
In most cases the 2nd AC is the only thing that is powered ny the second 120 volt leg.

[rmkrum]

And because he “knows what he is doing,” he didn’t bother looking at the box for the wiring diagram that makes it clear it’s a single pole 30 amp hot circuit with neutral and ground...

[gklott]

Originally Posted by Docv

do i need 240 volt for an 50 amp outlet or can i use 120? the only thing i know about electricity is to flip a switch

Recommend hiring a licensed electrician to look at your trailer and then decide what you need. Recommend matching your trailer's service configuration.

Refer your electrician to NEC Handbook Figure 551.46(C)(1), which shows the three types of receptacles permitted to supply your trailer.

73/gus

[dasams]

Originally Posted by TG Twinkie

In most cases the 2nd AC is the only thing that is powered ny the second 120 volt leg.

We have a 2018 27' FC and the loads are split between the two legs. We can see this by monitoring the current on my EMS surge protector. Also, I'm not sure I'm reading the wiring diagram correctly but it looks like the water heater, front AC, bath, refer and dining are on one circuit and the rear AC, micro, bedroom and inverter are on the other.

[Airhead2018]

We have a 2018 Classic 30' and I put in a 30 amp plug so we could get the frig running prior to taking a trip and for heat and AC (only one at a time) if needed. It works out great unless you want to test your systems capacity or do some troubleshooting with all system running then you will be missing the 50 amp. Having said that I would go with the 50 amp if you can as previously stated by Al and Missy. Also when doing your walkthrough at the dealer make sure you turn everything on at the same time to make sure it will work with a full load. Good Luck!

[dasams]

Originally Posted by Airhead2018

Also when doing your walkthrough at the dealer make sure you turn everything on at the same time to make sure it will work with a full load. Good Luck!

When we did our walk thru, the AS was connected to a household 20 amp extension cord so no way to check everything at once LOL

[uncle_bob]

Hi

IF you are wiring up a 50A (and not a 30A ) plug, it MUST be wired as 240V between the two "hot" lugs. The AS may not give a hoot about the 240V, but the CABLE and the Connector very much do care. You have 4 lugs on the plug, and 4 wires in the cable:

One is a ground and it should never have current on it

Two are hot leads

One is a return lead

The gotcha here is that you have two hots and one return. If both hot wires are in phase ( = no voltage between the hots, both read 120V to ground) the current in the return is in phase as well. If you get 50 + 50 in, then you get 100A through the return 50A connector pin and the return 50A wire in the cable.

If the two hot pins are out of phase you get 240V between the two hot leads. Each hot reads 120V to ground. Since they are 180 out of phase, when you run 50 + 50 in, you get zero through the return ( the currents cancel ).

One way *might* work if you never really pull any power. The other way *does* work and works under all combinations.

The point is that the 50A is really a 100A circuit if you are a 120V user. To be correct it needs to be wired to handle that full 100A.

Bob

[Airhead2018]

Originally Posted by dasams

When we did our walk thru, the AS was connected to a household 20 amp extension cord so no way to check everything at once LOL

Good Grief, another qualified Airstream dealer. lol