Electric Service - Montana Owners Club

dannyl · 05-31-2006, 08:49 AM

I'm really electric disadvantaged.
I have a friend who has invited me to camp at his house during a class reunion.
He said he had a outlet for a welder available. 220 volt.

Can anyone tell me what kind of electric is needed. Is it 220 or 110?

Like I said, I'm not afraid of normal 110 wiring, having done alot of it in my home, but I have no idea how it works. It must be MAGIC running through the wires.

Charlie · 05-31-2006, 09:03 AM

Most welding equipment that I have been around are 220V, not what you want to plug your trailer into.

Glass Guy · 05-31-2006, 09:04 AM

He probly has a low amp 220 line for his welder, the 50 amp service in your montana is also 220, but if he has a 20 amp service for the welder it will not be the same as a campground 50 amp service. You would be better of with a 30 amp 110 service. Roman

richfaa · 05-31-2006, 11:29 AM

The answer is simple...Do NOT plug your Montana into that outlet..there will be much smoke ...

cargary · 05-31-2006, 02:44 PM

I am not the sharpest tack when it comes to electricity either, but I do know from a friends unfortunate experience, that you do not want to plug into a 220 outlet. It will certainly cause some damage to your electrical appliances in your trailer. It could cause damage to your Tv's, microwave oven, possibly the AC unit and so on. It could also fry (burn up) your converter.
When at home, I plug my trailer into a 110 volt outlet and this gives me a trickle charge to my battery and allows me to use the lights and other low voltage items. It will not allow me to use the AC unit as outlet that I'm plugged into is only 15 amps and it is my believe that it takes at least 30 amp service to run the AC. I could be wrong on my assumption on this. If I am, someone that follows will likely correct me. Hope some of this helps.
Gary & Carole

Glass Guy · 05-31-2006, 04:18 PM

Gary you might get by on a 20 amp serice if the air is the only thing running, once the a/c is running it does not draw as much it is the initial start of the a/c compressor that draws so much. Roman

Montana_1240 · 05-31-2006, 06:03 PM

DannyL,

Your friend would have to change his existing welder receptacle for an 50-Amp RV receptacle. The one he has already is most likely different. Maybe a way folks wanting to make extra money can do so by labeling something for an RV, rather than regular household service. There’s a sharp increase in the cost of a welder receptacle, over one for an RV. And most often, they’re designed just enough different as to not be interchangeable. I know because I wired both, before going full-time.

Whatever you do…Do NOT plug into any average 220V outlet with the Monty’s cord! Even if it looks like it might fit. Don’t use a 30-Amp adapter, either.

The 50-Amp service most late model Monty’s use, (along with 50-Amp service for other RV brands,) is not really 220 in how it’s utilized. It’s 2 separate 110V circuits. Each with a different phase that would normally yield a 220V, 2-phase power line for heavy-duty equipment.

Effectively, what it gives the Monty is two separate, (though the supply’s circuit breaker brings both together at the breaker panel,) 110V lines. At the Monty’s circuit breaker panel, (depending on how the assembly line decided to wire it on any given day,) one of the 110V phases goes to about half the Monty’s outlets/hard-wired appliances, and the other 110V phase goes to the Monty’s other outlets/hard-wired appliances.

There’s a pretty clear description of what RV power is all about at this web address: http://www.myrv.us/electric/ Check out the links at the left of the page for what anyone wishing to learn about RV power needs to know.

If you use a regular 20-Amp outlet, remember that the longer the extension cord is, the more the voltage will drop. The heavier the cord, the less the drop. It might be enough to run you’re a/C on, but it’d be borderline.

Steve

c5racer · 05-31-2006, 06:30 PM

The guy that did our fence plugged his 220 welder into my 50 amp RV outlet and it worked just fine, the welder must use the 2 110 volts lines differently.

dannyl · 06-01-2006, 04:03 AM

Steve!!!
Thanks for the link. This information should be included in our owner's manuals so that we can check service connections.

I'll get this information to my friend so that he can make sure the service is correct. I'll start using my tester to check service.

I leave Saturday for a week in Juarez, Mexico working on a Presbyterian church there. I have been going there for the past 8 or 9 years and enjoy the fellowship and work. Can't take the RV this time (we use a 0.5 star motel).

Happy camping

VanMan · 06-01-2006, 04:06 AM

You can plug into your friend's 110 regular outlet with an adapter - you just won't be able to use everything you normally would at the same time (AC, microwave, hair dryer, etc.) Monty's are NOT 220 !! they are 110 - even the 50 amp !!!

Montana_1240 · 06-01-2006, 04:10 AM

Racer,

I realized, after posting that, that the wording was confusing.

The main gist of it is that the Monty doesn’t use 220V in any location on the rig. The plug-in, if plugged through a proper receptacle, with the right 220V device, will render 220V, by way of having the two phases.

If you were to measure between a Monty’s two HOT wires, you’d get 220V, because they’re of different phases. But since each phase is broken off when it hits the rig’s wiring panel, only 110V is at any specific point in the Monty.

I wonder how common the RV receptacle is when he’s doing business, and whether he carries multiple connections to deal with whatever power source he has at any site. Sort of like one of those “European Power Adapter” kits.

As stated at http://www.myrv.us/electric/

“The 50-amp service is a little more involved. It has 4 wires with two 125-volt HOT feeds. It is a misconception that the 50-amp RV service is something special. This service is a STANDARD 120/240 50amp 3 pole with 4 prongs used for numerous applications.

From this common service you can draw 120 or 240 volts. Each leg is 50 amps @ 120 volts. 50-amp X 120-volt = 6000 watts. But since there are 2 HOT 120-volt legs you have 6000 + 6000 = 12,000 watts to use in the RV or 50-amp X 240-volt = 12,000 watts when used as a 240-volt service.
Almost ALL 50 amp wired RV's use both sides of the service separately as 120 volt on each leg. Only a few mostly high-end coaches utilize the 240-volt from this same service by having a connection to both legs.”

I’m not sure what other applications would use the 50A plugs RV parks use, but that’s as clear as statement as one can get.

I’m just worried that someone might try to force a connection into a receptacle that isn’t wired the way RVs need. And if they were to do that, there could be major harm to the rig or the person.

Steve

Montana_1240 · 06-01-2006, 04:17 AM

Danny,

Glad to be of service. That link helped me wire my home before we full-timed.

I know that when I wired for 30A, (no A/C required…Just charger and appliances,) I had to go to the electrical shop to purchase the proper 30A receptacle. And sure enough. A “standard” three-prong 30A receptacle was about $6, while the RV plug, (which had an ever-so-slight difference in prongs,) was about twice that!

You’re lucky your friend has 220V, (2-Phase,) available. I have had invitations to stop in some places where friends said they had extension cords. (20-A.) That would have been fine in mild weather, but I’m not going to try that in hot, or even cold weather for any length of time. I like an A/C or this electric fireplace, along with the microwave, too much! (As you can extrapolate…I don’t do much dry-camping.)

Have him see what sort of receptacle he’s got, there, and if it’s the receptacle you need, and wired like the one on that website, you’re fine!

Steve

You may also like: