upgrading 30amp Class A wiring

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.

louzo1955

New member
Joined
Aug 8, 2017
Posts
3
Have an older Bounder and always wanted to be able to run both A/C's at same time. An electrician looked at my RV and has suggested I change from 30amp shore cord to a 50amp, install a two space 30amp breaker box in the basement compartment and connect L1 to existing wiring. With L2, install a second independent breaker box and move rear A/C, bathroom and bedroom outlets from existing house box to new. Now L1 will power kitchen forward (and front A/C), while L2 will power bathroom backward (and rear A/C.) He says its no different than using a 50amp to 30amp dogleg whereby your only using L1 from the 50amp plug and I'd never be able to draw more than 30amps off either L1 or L2 without blowing the 30amp breaker in the new breaker box. Also, that I won't have to upgrade any wiring since I haven't technically converted from 30amp to 50amp, rather just installing "two" 30amp services into coach with L1 powering front half and L2 powering back half. Should I have any concerns???? 
 
A better way would be to put the second a/c on a seperate 110 volt 20 amp line and power it independently. Most all parks have a 20 amp plug at the pedestal that is not being used.
 
That was my initial idea, but was asked why use two shore lines when this upgrade will still only require one.
 
How true. Thanks. Guess my concerns with this proposed upgrade was when I'd be in parks that only offered 30amp service I'd lose half of my coach power having to use a 50amp to 30amp dogleg. Still contemplating. Too, when dry camping my generator provides full power throughout and this electrician told me going his way I'd just always make sure to not connect shore power and run generator at same time, since there wouldn't be any transfer switch for back half of coach (of course when dry camping, there isn't any shore power to hook up to.) Also, about generator, he said the breakers on the generator would need to always be turned off when hooked to shore power to prevent any back feed. They are always off now when generator not in use anyway. 
 
SeilerBird's suggestion works great if you just want to be able to run a second A/C, but having a 50 amp service means you can also run your coffee pot and microwave while someone else is blow drying their hair. The key to switching over to 50 amp is make sure all the existing are fed from one leg, then add the second A/C and extra outlets etc. on the other leg.
 
An advantage to Tom's method of using a separate cord for the second A/C is that you can still use both A/C's even at 30 amp only sites, since they almost always have a 15/20 amp utility outlet too. I used that method on our previous 30 amp coach, and it worked quite well for us. Now we have a 50 amp coach, and I'm deciding on where to cut into the rear A/C wiring so I can do the same thing when we're using the dog bone adapter on a 30 amp site.
 
I'm with Dutch on this, if that 30a/20A site is a consideration.  Changing to a 50A cord means you have to use the 50/30 adapter at 30A sites and you won't be able to piggy back the 20A to it because of the shared neutral (GFCI on the 20A will trip).

If you typically will have 50A site, or if the a/c isn't a concern when you have only 30A available, then the single 50A power cord is slightly more convenient.
 
By going to the 50 amp service, and plugged in to a 30 source, you can choose which air conditioner to use. I have a 50 amp coach plugged in to a 20 amp service at home and can run either air conditioner. I can also run the small rear air and run the fridge on that circuit. Believe I'd rather have the 50 amp service myself. My rear air keeps my coach in the mid 70s on a 95 degree day, with the fan on high speed. That's good enough for me, I keep my house at 78 degrees and am comfortable with a ceiling fan running. 
 
louzo1955 said:
How true. Thanks. Guess my concerns with this proposed upgrade was when I'd be in parks that only offered 30amp service I'd lose half of my coach power having to use a 50amp to 30amp dogleg. Still contemplating.

Most 50 to 30 amp doglegs feed both sides of the 50 amp plug, so although you'll be limited to 30 amps total (the same as now), it will be distributed throughout the coach.

louzo1955 said:
Too, when dry camping my generator provides full power throughout and this electrician told me going his way I'd just always make sure to not connect shore power and run generator at same time, since there wouldn't be any transfer switch for back half of coach (of course when dry camping, there isn't any shore power to hook up to.) Also, about generator, he said the breakers on the generator would need to always be turned off when hooked to shore power to prevent any back feed. They are always off now when generator not in use anyway. 

Take out your transfer switch (they're close to junk anyway) and install a 50 amp outlet on the generator, located where you store your shore power cord.  When you unhook from shore power and stuff the cord into it's storage compartment,  plug the cord into the generator socket and you're ready to go, with the generator feeding the whole house when you start it.

Since the power cord can be plugged into either the shore power socket OR the generator socket, not both at the same time, there's no chance one will backfeed into the other.  Leave your generator breakers on since all they feed is the socket.

The only disadvantage is if you lose power while plugged in, you have to go outside and move the cord from the RV park pedestal to the generator before you can get generator power into the rig.  But how often does this happen?
 

Latest posts

Forum statistics

Threads
131,981
Posts
1,388,586
Members
137,726
Latest member
CampMike2270
Back
Top Bottom