30 amp vs. 50 amp in the driveway

omar1951 · 07-02-2021, 04:22 PM

I'd like to put an outlet outside the garage to connect power when the rig is in the driveway. While connected I want to be able to run an air conditioner, and perhaps the fridge but probably not the microwave/convection oven. The fridge is gas/electric. Will 30 amp service do the trick? I'm also confused about 50 amp service. Is that 120 or 240 VAC? As far as I know, all the electric in the coach is 120, but I am unsure about the microwave. The rig is a Thor Outlaw 2016.

Bob Denman · 07-02-2021, 04:34 PM

The entire "20 versus 30 versus 50" debate has been going on forever..

the safest bet is to simply put in the box that matches the service in your rig...
After all: you will eventually turn on enough stuff to pop the less setup.

I'll let the electrical gurus in here tackle 50 amp voltage question...

**EA37TS** · 07-02-2021, 04:42 PM

If your current coach is 30 amp and you have no plans of upgrading in the near future go with 30 amp. Running a 30 amp rig off a 50 amp service provides no benefit what so ever.

If you plan on upgrading to a 50 amp rig in the future install a 50 amp outlet. When I upgraded from 30 to 50 everything except the box had to be changed so it cost a few dollars.

DavidEM · 07-02-2021, 04:48 PM

First lets talk about 50A shore power. It has two hot wires, a neutral and a ground wire. If you measure between the two hot wires you will get 220V. If you measure from one of the hots to the neutral you will get 110V.

Larger MHs such as yours often use 50A shore power, so lets assume that is what you have, but they only use the 110V between the hots and neutrals, not the 220V between the two hots. This gives them two 50A, 110V supplies that power two strips of breakers or busses. Generally one buss of 110V breakers powers the routine things and maybe one A/C. The second strip powers the big A/C sometimes in the basement.

When you use an adapter to plug into 30A shore power you are only getting one leg of 110V power. It usually powers the first strip discussed above, most of the routine loads and an A/C but only to 30A. It does not power the second buss so the big basement A/C will not run.

So what do you want: full 50A power with all breakers functional. Then install a 50A/220/110V outlet and use your normal shorepower cord. If that isn't convenient, then install a 30A/110V outlet and use an adapter and live with only one A/C working.

If your home breaker box has available breaker space and particularly two opposite legs available side by side, the difference in cost is small- another breaker at the main panel, wire that costs a bit more for 50A and a bigger breaker and socket at the outside power box. But sometimes inside panels are almost full and even moving stuff around won't work, so you might be stuck with installing 30A, but not likely.

David

lwmcguire · 07-02-2021, 05:30 PM

Quote:

Originally Posted by Bob Denman

The entire "20 versus 30 versus 50" debate has been going on forever..

the safest bet is to simply put in the box that matches the service in your rig...
After all: you will eventually turn on enough stuff to pop the less setup.

I'll let the electrical gurus in here tackle 50 amp voltage question...

Exactly, and if you have a 30 amp install both 30 and 50 for the future

Many will have an EV in the future or a friend that needs a charge so double use out of the receptacle

standerson · 07-02-2021, 06:26 PM

Ford vs Chevy

9mm vs .45

30 amp vs 50 amp.

This could go on until we run out of alcohol.

We had 30 amp installed in our driveway. In the back of my mind, kinda wish we had gone with the 50 am so if we ever get the Super C or Class A, we wouldn't have to upgrade.

Bob Denman · 07-02-2021, 06:29 PM

Quote:

Originally Posted by standerson

...9mm vs .45...

That is not a debate...

"Old slabsides" still has an awful lot of life left in him.

pneumatics · 07-02-2021, 07:19 PM

Quote:

Originally Posted by DavidEM

When you use an adapter to plug into 30A shore power you are only getting one leg of 110V power. It usually powers the first strip discussed above, most of the routine loads and an A/C but only to 30A. It does not power the second buss so the big basement A/C will not run.

David

If you use a commercially available 30A male to 50A female adapter, these WILL supply 120VAC to both sides of the 50A. So you will have voltage everywhere but not enough power (Amperage) to use the 2nd AC.

Matching what you have on the MH to the power source is always the best route.

standerson · 07-02-2021, 07:47 PM

Quote:

Originally Posted by Bob Denman

That is not a debate...

"Old slabsides" still has an awful lot of life left in him.

Yep. .45 - Slow and fat wins.

Bob Denman · 07-02-2021, 08:08 PM

lwmcguire · 07-02-2021, 08:32 PM

Quote:

Originally Posted by pneumatics

If you use a commercially available 30A male to 50A female adapter, these WILL supply 120VAC to both sides of the 50A. So you will have voltage everywhere but not enough power (Amperage) to use the 2nd AC.

Matching what you have on the MH to the power source is always the best route.

Of the dozen or so i have been around they are all that way

Only way i know there sold

Beau388 · 07-02-2021, 08:41 PM

Quote:

Originally Posted by standerson

Yep. .45 - Slow and fat wins.

Nothing beats the guy with a Black Aces Tactical. I prefer the Bullpup.

Chateau_Nomad · 07-02-2021, 08:43 PM

Quote:

Originally Posted by DavidEM

First lets talk about 50A shore power. It has two hot wires, a neutral and a ground wire. If you measure between the two hot wires you will get 220V. If you measure from one of the hots to the neutral you will get 110V.

Larger MHs such as yours often use 50A shore power, so lets assume that is what you have, but they only use the 110V between the hots and neutrals, not the 220V between the two hots. This gives them two 50A, 110V supplies that power two strips of breakers or busses. Generally one buss of 110V breakers powers the routine things and maybe one A/C. The second strip powers the big A/C sometimes in the basement.

When you use an adapter to plug into 30A shore power you are only getting one leg of 110V power. It usually powers the first strip discussed above, most of the routine loads and an A/C but only to 30A. It does not power the second buss so the big basement A/C will not run.

So what do you want: full 50A power with all breakers functional. Then install a 50A/220/110V outlet and use your normal shorepower cord. If that isn't convenient, then install a 30A/110V outlet and use an adapter and live with only one A/C working.

If your home breaker box has available breaker space and particularly two opposite legs available side by side, the difference in cost is small- another breaker at the main panel, wire that costs a bit more for 50A and a bigger breaker and socket at the outside power box. But sometimes inside panels are almost full and even moving stuff around won't work, so you might be stuck with installing 30A, but not likely.

David

Great explanation of the wiring legs. The wire "run" from the house main panel to the 30/50 amp box/pedestal will be slightly more expensive for 50 amp; because you will have an extra 110v copper wire. As mentioned, you will have a higher rated dual breaker (basically a 220v 50amp rated piggyback) which is a little more... not much though. Then the 50 amp receptacle may be a couple bucks more for 50amp style vs 30amp.

Things to consider:
If your receptacle is fairly close (like a few feet) to your main service box, and NOT trenched underground, it would make sense to just do 30amp now. Upgrading to 50amp is fairly simple... different breakers, replace a short run of wire, and change out the receptacle. Not that much expense... especially if DIY.

Trenching an underground wire run an appreciable distance to a pedestal can get pricey... in which case I would definitely go with 50amp and use a 50-30 adapter... if there is even a SLIGHT chance you would ever buy a 50 amp rig.

Chateau_Nomad · 07-02-2021, 08:52 PM

9mm vs .45 ....
Center mass debate.
Kick back debate
Concealment debate
Green bottles vs brown bottles
Someone build a fire, get out the chairs and a cooler of cold ones... this may take awhile!