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SDCOToyhaul · 05-03-2015, 06:56 PM

So, was puzzled today how my Keystone Cougar could have everything 110 vac powered if I have a true 220 vac box. Pulled the fuse box cover today and sure enough, it is a true 220 volt box. A little differently configured from a house box but has two separate legs just the same. Guess why I questioned it was I am now running a 7500 watt, 220 vac gen set and it is wired to the 220 receptacle. I just wanted to insure that it wasn't powering everything using just one leg of the 220. Seeing now that the box is wired for 220, am puzzled how the opposite leg is getting voltage. Does the "power converter" do this??? Anyone have a reason or thoughts concerning this? Thanks

SDCOToyhaul · 05-03-2015, 06:58 PM

Guess I should have read my post before I hit send. lol Both legs are getting power when I am plugged into the home 110 volt circuit. Is this the power converter???

Knightab · 05-03-2015, 07:14 PM

A 50 amp coach has a 110 line to each side of the buss. All the breakers are 110 so you are just powering 110 stuff off each leg. If you were to replace a couple of the 110 breakers with a double pole you would get 220. The just always use 110 breakers so you can power more stuff as in air conditioners

Knightab · 05-03-2015, 07:15 PM

Quote:

Originally Posted by SDCOToyhaul

Guess I should have read my post before I hit send. lol Both legs are getting power when I am plugged into the home 110 volt circuit. Is this the power converter???

No it is not the converter, if you are using the dogbone adapter it just connects both legs inside the plug to power both buss legs.

FYI a converter producers 12 v from 110. An inverter produces 120 from 12 volt. Not all units come with inverters.

SDCOToyhaul · 05-03-2015, 07:52 PM

Still puzzled. I have added another power cord to the 5'er. Purchased a oem 220 volt plug from the dealer. Ran 6 ga wire from 5'er receptacle (in rear) to the front of the unit through conduit. My gen set is carried in the truck bed. This cable is a true 220. Now, I connected a 110 volt source into 1 leg of the circuit in the front portion. This is just home power to keep fridge running between trips. Somehow, I now have voltage to both legs??? Would think it would only power the leg it's wired to???

Knightab · 05-04-2015, 03:18 AM

Quote:

Originally Posted by SDCOToyhaul

Still puzzled. I have added another power cord to the 5'er. Purchased a oem 220 volt plug from the dealer. Ran 6 ga wire from 5'er receptacle (in rear) to the front of the unit through conduit. My gen set is carried in the truck bed. This cable is a true 220. Now, I connected a 110 volt source into 1 leg of the circuit in the front portion. This is just home power to keep fridge running between trips. Somehow, I now have voltage to both legs??? Would think it would only power the leg it's wired to???

Is this a 30amp coach? If so that is why in a 30 amp both legs are common not separate. 50 amp coaches have separate busses, careful you don't send 220 into coach and burn appliances up

wa8yxm · 05-04-2015, 05:06 AM

You need to study house power.. most everything in your house (lamps, TVs. Radio, Electric blankets, Clocks, Computers, Cell phone chargers and so on and so forth..If you have an electric rang PARTS of it, Fridge, Freezer, Microwave,, If you have an elctric cloths dryer PARTS of it, the washer.

All run on 120 volts

The Electric Range heat elements,,, the Dryer HEAT element and a central air conditioner...Those are 240 volt.

But the power to the house is 240 divided (As cooks say) into two 120 volt legs.

Same exactly as your motor home.

As to "Is it all on one leg" Depnds on who wired it.. I have seen some screwed up power panels.. and I've not seen that many power panels.

Knightab · 05-04-2015, 05:58 AM

Quote:

Originally Posted by wa8yxm

You need to study house power.. most everything in your house (lamps, TVs. Radio, Electric blankets, Clocks, Computers, Cell phone chargers and so on and so forth..If you have an electric rang PARTS of it, Fridge, Freezer, Microwave,, If you have an elctric cloths dryer PARTS of it, the washer.

All run on 120 volts

The Electric Range heat elements,,, the Dryer HEAT element and a central air conditioner...Those are 240 volt.

But the power to the house is 240 divided (As cooks say) into two 120 volt legs.

Same exactly as your motor home.

As to "Is it all on one leg" Depnds on who wired it.. I have seen some screwed up power panels.. and I've not seen that many power panels.

To clarify for him 240 is available in the coach should he put a double pole breaker in. Few motorhomes use 240 volts direct. What most 50 amp motorhomes have are (2) 30amp feeds one for each leg.

Steve Ownby · 05-04-2015, 06:05 AM

Quote:

Originally Posted by Knightab

To clarify for him 240 is available in the coach should he put a double pole breaker in. Few motorhomes use 240 volts direct. What most 50 amp motorhomes have are (2) 30amp feeds one for each leg.

Correct, except the 50 amp motorhome service is two 50 amp feeds not 30 amp. A 50 amp coach has 100 amps available to the coach.

Steve Ownby
Full time since '07

Knightab · 05-04-2015, 06:15 AM

If you have a 50 amp coach and only have 1 leg from your generator connected and you are not using a dogbone something is hooked up wrong.

Clarify when you say you bought a 220 volt plug from the dealer. Are you speaking of the RV dealer?

Knightab · 05-04-2015, 06:48 AM

Quote:

Originally Posted by Steve Ownby

Correct, except the 50 amp motorhome service is two 50 amp feeds not 30 amp. A 50 amp coach has 100 amps available to the coach.

Steve Ownby
Full time since '07

There is not a 100 amps available because the breaker limits it to 50 amp load. You are using 1 50 amp double pole in the box which is spit to 2 busses. Either leg pulling more than 50 amps singular or together will trip the breaker.
PS: you are right about it being 50 amps per line on the 30 amp circuit the breaker is the determining factor but the rv is still limited to using only 50 amp period being limited by the breaker there also.

SDCOToyhaul · 05-04-2015, 07:22 AM

Yes, I know house power. Only dryer, range, etc. actually use 220 volts. Still, you have two 120 volt legs. This 5'er is a 50 amp service though nothing in it uses 220 volts. If you were to drop a leg in a home, nothing 220 would work and only 1/2 of 120 volt appliances or outlets would be active. Will look again today. Got to be a really simple answer. Maybe if I just find my mind. lol Just too many projects at once.

wa8yxm · 05-04-2015, 03:17 PM

Quote:

Originally Posted by Knightab

To clarify for him 240 is available in the coach should he put a double pole breaker in. Few motorhomes use 240 volts direct. What most 50 amp motorhomes have are (2) 30amp feeds one for each leg.

WRONG.. They have a 50 amp 120/240 volt feed Same exactly as a house would have save most Sticks and Bricks have 100, 150 or 200 amp feeds.. It is IDENTICAL to house power.

It is not two 30 amp feeds, it is two fifties..

It is not 100 amps at 120 volts it is 50 amps at 240 volts divided. (Works out the same as 100 at 120 but it's not).

And there are very good reasons for doing it that way.. Which I have typed out several times (has to do with wire size and voltage loss you need less copper, and you loose less voltage).

The reason I am so insistent on this is that failure to get it right can cause damage, up to and including a fire which can completely destroy an RV.

I apologize if I sound harsh but one group of folks I hope NEVER to do business with.... The Fire Department.

SDCOToyhaul · 05-04-2015, 10:06 PM

Well, as I said earlier, the memory ain't what it used to be. lol I had forgotten that I had installed a jumper lead across the 30a 220v terminals on the genset plug so as to be able to power all the outlets with one 120 volt circuit.. Did that so that I would have voltage to the garage area to be able to use the ramp lift hoist I installed. Yes, as to having two 110 volt legs to the box. The way the legs are laid out, it still only has 110 volt capability. The legs run horizontal and are split in the center so as to have the two 120 volt legs only. There is nothing in the unit that uses 220 volts. Thanks again for all your ideas and input.