Right now we have a Class A Winnebago Adventurer with a 50 amp service which runs everything plugged in or with the generator.  We are thinking of buying a Jayco Altante 31V which is a smaller RV 32' but only has a 30 amp service.  It has two 11,000 btu air conditioners and want a convection/microwave installed as well.  Will the 30 amp run both airs and the convention over at the same time?  Will it only run one air at a time?  The sales people say yes, but we all know how that goes.  I can't find anything on it really.  We have been full-time since 2002 and our RV is breaking down and want to trade for a smaller.  The Alante drives nice and love the floor plan, but the 30 amp is a concern.  Also will a Ford V10 320 HP engine have trouble going up hills while pulling a car?

IMO, since the coach comes with the 2 air cons, it is designed to run both at the same time.  If it does not come with, or have a convection micro as a factory option, it is not designed for one.  Meaning it is not designed to run both airs and a convection micro at the same time.  You might be able to run one air with the micro, but possibly not both airs and the micro.

As for towing up hills, it depends on how steep the hills and how heavy the toad.  Of course, you should also check how it will handle going down the other side.

It is not possible to give certain answers to the question of what you can operate at the same time with the limited amount of information given because not all appliances of the same type require the same amount of electricity. There are several things you need to know in order to understand what you are looking at. A 30a RV has a 3 pin power cord with one hot, one neutral, one ground pin. The 30a power is the most that you can ever draw between the hot and neutral pins and it is limited by a single circuit breaker. The ground pin is there for safety.

In a 50a power plug there are 4 pins, 2 hot pins(L1 & L2), one neutral pin, and one ground. The main power circuit breaker for 50a is actually two 50a circuit breakers that are mechanically tied together and so the total available power with 2 hot and 1 neutral is now 100a, or more than three times as much as for the 30a plug. What you actually have is 2 different sections of power distribution that each can supply a maximum of 50a of power. The result is that in practical applications your 50a RV can actually be using at least 80a of power at one moment in time, while the 30a is limited to just that. 

Looking at your proposed RV, there is little likelihood that you would be able to run everything in the RV on 30a of power, but just how much you can operate depends on the requirements of each item. RV air conditioners typically use anywhere from 6a of power to as much as 13a of power once they are operating, with the amount required depending on the size of the air conditioner and its age. Newer air conditioners are much more efficient than older ones and so require less power. In addition, most likely the 2 air conditioners are not the same size as most RVs have a large one in the front for the living area and a smaller one for the bedroom. The other big load in any RV is the microwave and those also vary in power required. In general, a smaller one will need less power than a larger one. 

I would suggest that you ask them to plug the RV in and then run the air conditioners both at the same time. Once they are both operating, put a glass of water into the microwave and see if you can heat it up without shutting something off. My best guess would be that if this is a new or near new RV you can probably use both air conditioners at once, or 1 air conditioner and the microwave, but probably not all three at one time. If it has an electric mode for the water heater, that would be another item that might not work with two of the other loads. You can live comfortably with only 30a of power as many people do so but you will probably have to learn to manage that power use.

  On 10/20/2019 at 4:42 PM, Downsizing said:

Also will a Ford V10 320 HP engine have trouble going up hills while pulling a car?

I am wondering what engine your Adventurer is powered by? The Ford of that era was 310HP backed by a 5 speed transmission. The new engine has 320 HP with a 6 speed transmission. Since it also powers a smaller RV I would expect that it would do as well and probably better than your Adventurer did. It won't win any races, but why would you want to do so?

20 amps!

? some jackass hadta say...

now back to the experts...

Most electrical engineers design circuits at no more than 80% of capacity.  This is a safety factor.  If RV's followed that then 24 amps would be safe.  That is only about 2900 watts.  Many people live with 30 amps but it can be a problem if you are not used to it.  I think 30 amp service is just another example of the RV industry cutting cost despite the safety concern.  The average coffee pot uses around 1000 watts and the microwave may well use 1500.  Add in the converter and that may be at the safe limit.  I would have to think long and hard before I would go back to 30 amp service.

You will lose 70Amps.

  On 10/21/2019 at 12:19 AM, Randyretired said:

Many people live with 30 amps but it can be a problem if you are not used to it. 

We managed on 30A for 2 months this summer but we were fortunate to be in a location where A/C was rarely needed (Maritime Canada).  Our biggest headache was that our hot water is electrically heated and we often turned it off at dinner time so we had enough power for cooking, lights and a TV.  Fortunately, we have a very nice residential-quality propane cooktop, so not using our induction burner (as often) wasn't too much of a hardship.  But when had to turn on the A/C for a couple of days that complicated things immensely and we could only operate one A/C unit on 30A.

Edited October 21 by docj

Just to help in calculations a standard outlet is wired for 15amp, at full 15amps that is 1800 watts. This assumes you are getting a full 120 volts, many camp grounds have voltage lower than that, especially when the park gets full and everybody is running AC.

Lower voltages pull more amps for the same load.  EMS systems like the Progressive units cut power if the supply voltage drops below 104 volts. This happens to me a couple of times a year.

Typical power consumption of appliances

Then take into consideration 30A CG supply = 3,,600W @ 120VAC;  50A CG supply = 12,000W @ 120VAC, keeping in mind there are 2 hot legs supplying power instead of only 1 on a 30A circuit, this is actually 100A service, without 220VAC available inside the main panel-  some high-end coaches do use 220VAC inside.

filthybeast, I have my Progressive EMS set to 108VAC minimum, 132VAC maximum.

Edited October 21 by Ray,IN

I would look around for something of similar size that comes with 50AMP.  We have a 50AMP RV and know how to live on 30 or 20AMP, but we are always glad to get back to 50AMP where we can do what we want without as much compromising.  

Couldn't agree more with Bill, once you get use to having 50amps, you always feel like you are having to make do when on 30 amps.   Particularly when it comes to A/C.  In 100+ temperatures, it is so nice to have both A/Cs running, and the coach is at a very pleasant temperature inside.  When on 30 amps, just one A/C running, we can maintain inside temperature at around 90 with an outside temp of 116 (no, not in the desert, that was in Cloverdale, CA - northern Sonoma County - 3 years ago on Labor Day) - you can exist, with extra fans going, but it isn't pleasant.

Now, if we are not in someplace with temperatures near 100, we can get along on 30 amps with just a little tweaking of our normal routine.  Things like switching water heart electrical off and only using propane, or turning A/C off (compressor part, keep the fan going) while using microwave.  Of course when it is that hot, cooking is done out on the grill,  use the w/d only at night when A/C isn't running or use park Laundromat.   

Edited October 22 by Barbaraok

  On 10/20/2019 at 4:42 PM, Downsizing said:

  It has two 11,000 btu air conditioners and want a convection/microwave installed as well.  Will the 30 amp run both airs and the convention over at the same time?  

Highly doubtful.  What usually happens in high-amp situations is the plug gets hot and melts.  The breakers never seem to stop that.

What you can use in a 30 amp RV is no different than what you can use when you plug your 50 amp RV into a 30 amp outlet.

I have a 30 amp trailer and my rule of thumb is I can use two large heat producing appliances at the same time.  That's my single air conditioner plus one other heat producer like the microwave, the electric side of the water heater or any plug in appliances like an electric skillet, hair dryer, etc. Usually I leave the electric side of the water heater off and just use the gas burner.  

The refrigerator also uses a fair amount of power in electric mode but this hasn't been an issue for me.

Two air conditioners will have to be connected to a power management system so both compressors don't cycle on at the same time and running both will preclude running another major appliance.  Check your trailer, some include a switch that allows power to go to the front or rear air conditioner but not to both at the same time.  Or one air conditioner vs. the microwave, etc.

The rest of your loads, the lights, TV, etc. don't use enough electricity to worry about and can be used without restriction.

Living on 30 amps doesn't bother me, I just have to be aware of what I'm using.  But if you don't want to do this, get a 50 amp RV.

Edited October 22 by Lou Schneider

We had a 30A and 50A for 16 years of full-timing.  We enjoy public parks and they will often have 30A rather than 50A.  We had absolutely no issues  You'll soon learn what you can and can't use at the same time.  It also depends on the temps you stay.  If only being able to use one AC then close off the bedroom where you won't be during the day and just cool the living area.  Around 7pm turn off the liv. area and cool the bedroom.  You'll be surprised how both can be cooled in the evening with only one AC running.  Use the bedr. one all night but the living area will still cool down.  Also, a Fantastic fan on all night with one or two windows cracked a bit really helps at night.

Get the RV you'd be happy with and things will work out for the small times of inconvenience.

  On 10/20/2019 at 11:07 PM, noteven said:

20 amps!

? some jackass hadta say...

now back to the experts...

What did you mean by that???? I saw no 20 Amp comments.