Electric for air conditioning

One other thing ... I see you thought of simply swapping a 30 amp breaker into the spot where a 20 amp now lives.

There are still folks who make house calls.. For example the Fire Department

Do not do this.. or they may.

A couple of things that haven't been mentioned here that might be useful for the OP:
When you're trying to run the AC and/or microwave, don't worry too much about the fridge. It's only going to use ~200W (<2A) when it cycles on.

Depending on how long you expect the RV arrangement to last, you may want to consider installing a new outlet like some have suggested. Regardless of who does it, you should check for yourself to see that it's done right. Given the relatively small difference in cost between a 30A and 50A installation (a little more in wiring mainly), I'd probably install 50A. You'd have to run new wiring and pay about as much in labor to upgrade at a later date.

Perhaps the biggest thing to keep in mind (and that's often overlooked) is what the converter is drawing to keep the batteries charged. On a normal 30A service, I regularly run two air conditioners--but I do it with the converter either off or plugged in to a different circuit. In your case, with only 15 or 20A to work with, you should be able to run one air conditioner (assuming sufficiently large wiring to the RV) without issue. You might consider a habit of turning off the converter in the morning, and letting the batteries recharge overnight.

That last bit--and power management in general--might sound a little bit complicated, especially for your mother to manage herself. But if you put together a list of appliances and what they consume, and explain to her what the connection can handle, I'm sure it could be done.

Vulcan Rider wrote:

kaydeejay wrote:
No reason for ANY electrician to run a 4-wire cable to a 30A 3-pin receptacle under ANY circumstances so your question about what to do with the 4th wire becomes irrelevant.

The other side of that coin is:
There is NO reason for any electrician to be screwing around with a double ganged breaker when installing a single 120 V outlet.....no matter how many wires he intends to run to the outlet.

If he doesn't KNOW about 30 amp trailer service, he should FIND OUT instead of guessing.

Caveat emptor (let the buyer beware) pretty much applies here, I think. This is especially true if the owner assumes too much of the responsibility by trying to tell the electrician what to do instead of telling him what service he needs.

No argument with that except it is not unreasonable to expect a licensed electrician to know what he is doing without having to be instructed. Many insurance claims have been paid on behalf of the pros who got it wrong!

Vulcan Rider wrote:
Others have covered the electrical requirements.

If this was MY 97 year old mother in the condition you describe, I think I would be looking for an "assisted care" facility close by.....maybe near to Dad's rehab facility.

My gut feeling is that this really isn't such a good idea.

X2 My mom was 99 when she passed. She was pretty mobile, and had no arthritis, but people in this age category are subject to falls. Living in an RV, which is more cramped than a S&B will put mom at increased risk of injury in the event of a fall.

kaydeejay wrote:

No reason for ANY electrician to run a 4-wire cable to a 30A 3-pin receptacle under ANY circumstances so your question about what to do with the 4th wire becomes irrelevant.

The other side of that coin is:
There is NO reason for any electrician to be screwing around with a double ganged breaker when installing a single 120 V outlet.....no matter how many wires he intends to run to the outlet.

If he doesn't KNOW about 30 amp trailer service, he should FIND OUT instead of guessing.

Caveat emptor (let the buyer beware) pretty much applies here, I think. This is especially true if the owner assumes too much of the responsibility by trying to tell the electrician what to do instead of telling him what service he needs.

Vulcan Rider wrote:
I don't know about the incidents that you quote but as this goes along farther it gets even more unbelievable.

The 30 Amp receptacle has 3 conductors, right ??
And a 220 receptacle has 4 conductors, right (hot, hot, neutral and ground) ??

If the "electrician" runs two hots (4 wires) to a 3 conductor receptacle.....where does he connect the 4th wire ??? Or which of the remaining two conductors does he connect to the one remaining lug ??

I can see a rank amateur screwing this up but not a real electrician.

'Fraid not! The 30A RV receptacle and the 30A welder/dryer receptacle both have three pins. The two grounds are a different shape though.
As I said earlier, the connection at the receptacle MAY be identical, it's how the wires are connected at the panel that makes the difference.
30A RV (110V) = 1 breaker, one hot, one neutral (plus ground)
30A Welder etc (220V) = double breaker, two hots, one ground. NO Neutral.
No reason for ANY electrician to run a 4-wire cable to a 30A 3-pin receptacle under ANY circumstances so your question about what to do with the 4th wire becomes irrelevant.

Vulcan Rider wrote:

kaydeejay wrote:

Most electricians do not know what a 30A RV receptacle is and think it should be wired the same as for a welder!

I don't know about the incidents that you quote but as this goes along farther it gets even more unbelievable.

The 30 Amp receptacle has 3 conductors, right ??
And a 220 receptacle has 4 conductors, right (hot, hot, neutral and ground) ??

If the "electrician" runs two hots (4 wires) to a 3 conductor receptacle.....where does he connect the 4th wire ??? Or which of the remaining two conductors does he connect to the one remaining lug ??

I can see a rank amateur screwing this up but not a real electrician.

The problem is "What is a real electrician". As a RV professional(36 years), I have made a good amount on money from so called licensed electricians miswiring both 30 and 50 amp RV plugs. Texas seems to have the weakest licensing for electricians. I get calls all the time from so called professional electricians asking ME how to wire a 30 or 50 amp plug. The miswire in Texas is an epidemic. I always tell the RV'er, IF the so called electrician has to call ME, then he is not a Professional Electrician with the knowledge to do the work. ANY licensed/bonded electrician should KNOW what a 30 or 50 amp RV service is and what is required for the installation. But, sadly, a LOT do not. Doug

A friend was faced with a not too dissimilar event. He chose to run a large extension cord from the house breaker box to the rig. But that isn't cheap.

Maybe it's time to consider having an electrician run a dedicated 30-amp line to a new power post beside the rig.

I side with Vulcan Rider. The infirm don't need much of a push to have a calamity. I have experience as I am almost there myself.

Vulcan Rider wrote:

kaydeejay wrote:

Most electricians do not know what a 30A RV receptacle is and think it should be wired the same as for a welder!

I don't know about the incidents that you quote but as this goes along farther it gets even more unbelievable.

The 30 Amp receptacle has 3 conductors, right ??
And a 220 receptacle has 4 conductors, right (hot, hot, neutral and ground) ??

If the "electrician" runs two hots (4 wires) to a 3 conductor receptacle.....where does he connect the 4th wire ??? Or which of the remaining two conductors does he connect to the one remaining lug ??

I can see a rank amateur screwing this up but not a real electrician.

Not right. Many 220's have no neutral. If there is no need for 110, there's no need for a neutral. Electric dryer, air compressor, etc.

http://www.how-to-wire-it.com/wire-a-dryer-outlet.html

The issue is the 3-pin dryer 220 and 3-pin RV 110 look similar.

EDIT: There seems to even be confusion across the net on what a 220 3-pin dryer plug has. Some say hot,hot,neutral and others say hot,hot,ground. Regardless, either one would put 220 onto the hot,neutral of the RV plug if an uninformed electrician wired the RV plug like a 3-pin dryer one.

Here's a site with the NEMA chart showing various configurations. http://www.kellyhayes.com/images/tools/NEMA%20straight%20blade%20configuration%20chart.jpg

Note there are 3-pin 220 only like 6-30R and 3-pin 220/110 like 10-30R. One has no neutral. One has no ground. The style with no neutral (6-30R) uses a round pin for ground just like the 110V RV style 30A receptacle. Those are the 2 that can get confused.

kaydeejay wrote:

Most electricians do not know what a 30A RV receptacle is and think it should be wired the same as for a welder!

I don't know about the incidents that you quote but as this goes along farther it gets even more unbelievable.

The 30 Amp receptacle has 3 conductors, right ??
And a 220 receptacle has 4 conductors, right (hot, hot, neutral and ground) ??

If the "electrician" runs two hots (4 wires) to a 3 conductor receptacle.....where does he connect the 4th wire ??? Or which of the remaining two conductors does he connect to the one remaining lug ??

I can see a rank amateur screwing this up but not a real electrician.