50 Amp Service

[Broome101]

OK NJ Hillbilly I just want to get this correct when I do this electricity does not scare me since I deal with it everyday but on larger scale 3 phase stuff. I have always been told that all RV's are 120 VAC so if i wire into my house a 50 Amp breaker red and black to hot sides white to common and green to neutral or ground and same at the 50Amp RV receptacle i should be fine using the 50Amp power plug from the RV.

[owenwetzel]

NJ Hillbilly. At my main switch box in the lamp table between recliners there are 2 sets of 30amp double pole breakers. All 4 breakers are marked 30amp.

[Montana_2785]

quote:Originally posted by owenwetzel

Well gentlemen I have a 2000 3280rl there is a closet between toilet compartment and bed. In this closet the are hot and cold faucets and a drain line next to them is a 110v outlet. IN THE CEILING THERE IS A (I QUOTE FROM THE COVER OF RECEPTACLE)Leviton 30amp 125/250 volt 4 wire outlet. I took the cover off and it has a red, a black, a white, and a bare copper wire to ground all are no. 8 wire if that is not a 240 outlet then my electrical experience has taught me wrong. Oweners manuel did not mention this at all.

WOW!!!!

Did you purchase this new or used? I'll bet used...

As long as you are plugged into a 50amp park plug it will be OK. The moment you use a 30amp to 50amp adapter cable to plug into a 30amp park plug, you won't have 240V on that outlet anymore. If you really had a 240V appliance, it would be toast....

If you are the original owner, then I'd seriously suggest that you call Keystone with your VIN and see what is up with that outlet.

Eric

[owenwetzel]

Eric, we bought it brand new in Feb. 2000. All wiring is original. We do not have any w/d's or any 240 appliances nor do we expect too. That is why I brought up the 240 statement. National Electric Code states there has to be a ground wire on all receptacles. If you look at connectors there are 4 wires. 1 each for each 120, 1 neutral, and 1 ground wire. Without this your ground fault circuits would not work. You would have to drive an 8 ft. rod into groun for it to opperate.

[Montana_2785]

quote:Originally posted by owenwetzel

Eric, we bought it brand new in Feb. 2000. All wiring is original. We do not have any w/d's or any 240 appliances nor do we expect too. That is why I brought up the 240 statement. National Electric Code states there has to be a ground wire on all receptacles. If you look at connectors there are 4 wires. 1 each for each 120, 1 neutral, and 1 ground wire. Without this your ground fault circuits would not work. You wood have to drive an 8 ft. rod into groung for it to opperate.

In that case, I'd seriously suggest you ask Keystone what is up with a 240V outlet in an RV. I don't see HOW the factory could possibly put that in knowing how "240V 50amp" RV's are commonly plugged into "120V 30, 20 or 15 amp" service.... I'd think it would be liability city

I'd love to know what option included that

Eric

[owenwetzel]

We have ran 5er from 120v at home and some small campgrounds as weel as a 5k generator with no problem. As long as we had a 20amp service. When we did this we used 12v lights and gas for w/h & frig. Supplied AC ok. I will call Montana asap to get explaination though.
I guess this is one of the changes made since we bought our 5er. I need to find out just how many changes have been made.
Thanks for the info.

[Montana_2785]

quote:Originally posted by owenwetzel

We have ran 5er from 120v at home and some small campgrounds as weel as a 5k generator with no problem. As long as we had a 20amp service. When we did this we used 12v lights and gas for w/h & frig. Supplied AC ok. I will call Montana asap to get explaination though.
I guess this is one of the changes made since we bought our 5er. I need to find out just how many changes have been made.
Thanks for the info.

As long as there are no 240V appliances plugged into that 240V outlet inside your rig, there will be no problem. The problem would be IF there was a 240V appliance plugged in. AFAIK, there are NO 240V "RV" appliances at all. However, since you have the plug, I would think that a person would normally then think it was usable.

I think that actually plugging a 240V appliance into your internal 240V outlet would be a disaster....

Eric

[Charlie]

I have been montoring this thread for some time and think that I understand the whats and hows of Eric's reply to Thunderman on the 50 amp service:

Thunderman, 50 amp service is, in fact, two 120V legs. Both legs are present inside your RV circuit breaker box. Now, if you have a 30amp service and you use a 30amp to 50amp adapter cable, THEN the single 30amp leg will be placed on the two 50amp legs inside the RV.
Eric

My question is if you do not have a second A/C and washer/dryer and the load requirements on the coach are no greater than what a 30 amp cord can supply would it be better to use the 50 amp cord if one was at a place where voltage was borderline, IE does the 50 amp cord have larger wiring and would allow better flow of current or is it just larger because it has an extra wire to handle the second 110V leg? If so, then it would be easier to hook-up and not wrestle with the monster.

[Montana_1240]

Broome101,

When I was readying to get my Monty home, I knew it couldn’t be close to the house, where I had the builder reserve a space in the breaker box for a double pole 50-Amp receptacle, and didn’t want to buy a long extension, since we wouldn’t need it after a few months. So I installed a standard single pole 30-Amp receptacle. We never had to run the A/C since we lived in Fairbanks at the time.

But since you need more juice, (and I’m going to assume your house’s power box is rated for the added receptacle,) I’ve had a neat web page linked into my Favorites for a while.

http://www.myrv.us/Pgs/RV/50amp.htm

This goes over the whole story.

Enjoy it. Be safe. Happy camping!

Steve

[Fordzilla]

Gyro, thanks for the link. I am looking to put a 50amp pole out in the backyard where we park the trailer and this will help a lot.

[Dustytuu]

My husband is an electrican but he is at work at the moment. I will have him look at this post tomorrow. If you still need help. He could tell you how to do it. He is licensed and done this for over 40 years. Commerical and residental work.
Dusty

[Montana_2785]

quote:Originally posted by Charlie

I have been montoring this thread for some time and think that I understand the whats and hows of Eric's reply to Thunderman on the 50 amp service:

Thunderman, 50 amp service is, in fact, two 120V legs. Both legs are present inside your RV circuit breaker box. Now, if you have a 30amp service and you use a 30amp to 50amp adapter cable, THEN the single 30amp leg will be placed on the two 50amp legs inside the RV.

Also, when you actually have 240V, the sine wave of the two legs is 180 degrees out-of-phase from each other. This is because each leg is on either side of a center tapped transformer.

When you apply a single 30(or 20 or 15)amp leg onto our RV 50amp system, the sine wave on the two will be IN phase (or 0 degrees out-of-phase).

quote:
Eric

My question is if you do not have a second A/C and washer/dryer and the load requirements on the coach are no greater than what a 30 amp cord can supply would it be better to use the 50 amp cord if one was at a place where voltage was borderline, IE does the 50 amp cord have larger wiring and would allow better flow of current or is it just larger because it has an extra wire to handle the second 110V leg? If so, then it would be easier to hook-up and not wrestle with the monster.

Short answer to your exact question: There would be no difference unless your 50 amp cord was on the order of 60-70 feet long or more.

The true 50amp circuit consists of TWO 120V 50 amp circuits. That is TWO 50amp circuits for a total of 100amps worth of 120V usage. Yes you read that right, a true 50amp service can supply more than 3 TIMES THE POWER of a 30amp service!!! So each wire inside the 50amp cable is actually heavier wire because each is capable of conducting 50 amps in addition to being more wires.

Since I have the older quasi 50amp system in my unit, it really doesn't matter which wire I use as my internal breaker will pop before I can draw 50 amps. So, it would be better for me to go ahead and leave my 50amp cable behind right now. It isn't long enough to make any difference in voltage drop. A 30 amp cable does me just fine.

If you really have a true 50amp system on the newer Montana, then you would have two advantages as I understand the wiring.

1) The newer units balance the load of the various appliances between the two legs so you can actually USE the power in both legs even if you don't have a second A/C or W/D. In other words, the true 50amp Montana is wired so that there is more than just the second A/C and W/D on the second leg. I have the second 20amp leg but I can't use it for anything right now (I plan on fixing that )

2) PLUS one leg has a 20 amp, and the other leg a 30 amp advantage over someone with the older quasi 50amp (the 30/20 split). In that case, if you enjoy using the electric water heating element in addition to microwave and first A/C and hair drier and small kitchen electrics and.... then you would definitely benefit from using your 50 amp cable.

If your happy to live simply and are willing to manage your power usage to fit in a 30amp supply, then feel free to use your 30 amp cable. Where I run into problems is in cold weather when I'm trying to run a couple of electric space heaters. In warm weather, we don't find it difficult to live within a 30amp budget.

Eric

[Broome101]

Gyro, That's a great link just what I was looking for in the first place. Thanks

[NJ Hillbilly]

quote:Originally posted by Broome101

OK NJ Hillbilly I just want to get this correct when I do this electricity does not scare me since I deal with it everyday but on larger scale 3 phase stuff. I have always been told that all RV's are 120 VAC so if i wire into my house a 50 Amp breaker red and black to hot sides white to common and green to neutral or ground and same at the 50Amp RV receptacle i should be fine using the 50Amp power plug from the RV.

Yes, that is the way mine is(black and red hot). The 2 110v legs are out of phase (as Eric stated) and they use the white as the common. 220v receptacles don't use a common because the power waves are out of phase and work off each other.
This is why some 220v 15 amp receptacles have one blade perpendicular to the other "- I" so a 110v appliance that needs the common for a return path cannot be plugged into it.
I believe some large busses do use 220v for hydronic heat but am unsure. As for us, there is no need and the outlet in the dryer area of Owen kinda stumps me.

Owen, the receptacle in Your closet has a ground, it lacks a common. The common would be required for it to be a 110/220 receptacle, a 220 only is 3 wires.


John

[Charlie]

Eric-
Thanks for the reply, understand the system even better now and the why of tripping a breaker while on 30 amp service even though I was using the larger cord. Since I have one of the newer units I will use the 50 amp cord where supply is available, otherwise sites that have only 30 amp I will leave the monster in the basket and watch the load.

[sreigle]

quote:Originally posted by owenwetzel

If you do not have w/d a 30amp would be enough.

Just wanted to point out we run our washer and dryer when connected to 30 amp power. We run the AC at the same time both washer and dryer are going. We cannot add an additional high-draw appliance, like microwave, to the load without popping the breaker but can run those three plus the fridge, lights, 2 laptops, etc., without problem.

Like Eric, we have the older 50-amp system that is essentially 30 amps to the coach and 20 to the second AC prep (don't have the second AC unit though).

Awhile back I spoke with Keystone to find out if there's value in my switching to the newer converter and breakers. They commented it might help a little but not like I think since the newer units have more circuits to spread the load over and we'd still be limited to a smaller number of circuits.

[Broome101]

Gyro, Have one other question went to look at the Amp service you had on the link. Understand it fine but it claims to be a 70 amp service is the 50 amp 2 pole breaker OK to wire from box to this service box?

[owenwetzel]

John & Eric. I called Keystone today and asked them why I have 2 sets of 30amp double pole breakers. The 220 receptacle is the same model as the ones put in my kitchen and laundry room by electrition when we had our home rewired before putting up for sale. The dryer had 1 red, 1 black,1 white to common groung, and grounding wire for grounding terminal of dryer.
I asked for a wireing diagram and was told they could not give one because they try to put out 20 units a day and there is no uniform wireing layout for these units. Am calling another person tommorrow.

[Dustytuu]

This is reply to the original question....
Either use # 6 wire or 4 wires # 6 cable wire.

Make sure your house will handle a 50 AMP plug. House needs at least a 200 AMP service to handle this. Other wise it could be a big problem !! Or could start popping the main breaker in your house.
I think you should call an electrician.

220 is actually two 110 lines.
Don

[Montana_1240]

quote:Originally posted by Broome101

Gyro, That's a great link just what I was looking for in the first place. Thanks

Broome101,

You're welcome. There can be nothing more frightening than to plug into the unknown.

I've been messing with electrical stuff since I was a kid, and still need it 'splained, the way that page does, from time to time.

Happy Camping!
Steve