30 amp vs 50 amp sites

[Dr. Dolittle]

I'm trying to make reservations for mid May at a nearby state park that my wife wants to visit. All of the dates I've tried show only 2 sites available, both showing 30 amp service. I'll be parking a TT with 50 amp rating, dual air conditioners.

If we're careful with other electrical loads could we run both A/C units? Is there a CB to pull or some other way to only run one A/C unit?

We don't have the TT yet or I'd look for the CB solution myself. Also, it might not be hot enough at night that time of year to even need the A/C but I'm trying to plan for all possibilities.

[jrollf]

Run both on 30 amps... It 'depends'...

How large are the AC units? If they are two 15k BTU units it may not or may not be possible. Not knowing which ones you have makes it harder to guess. Roughly the running amps will be in the range of 13 to 16 amps, so if yours is on the higher side thats around 32 amps, which if the breaker doesn't trip, the plug I likely to get hot. You really are not supposed to pull Max amps from a breaker continously.

but.. you also have startup amps which are around 16 to 18 amps, so if both started at the same time you could pull 36 amps, likely kicking the breaker. Startup in rush can be reduced by adding 'sof starts' to the AC units.

On to your second question... Every dual AC unit I've seen you can run one unit at a time and leave one off, for this exact reason (to run off 30 amp service).

[NewBlackDak]

Originally Posted by Dr. Dolittle

I'm trying to make reservations for mid May at a nearby state park that my wife wants to visit. All of the dates I've tried show only 2 sites available, both showing 30 amp service. I'll be parking a TT with 50 amp rating, dual air conditioners.

If we're careful with other electrical loads could we run both A/C units? Is there a CB to pull or some other way to only run one A/C unit?

We don't have the TT yet or I'd look for the CB solution myself. Also, it might not be hot enough at night that time of year to even need the A/C but I'm trying to plan for all possibilities.

There is no reason to run both ACs at night. Run the one in or closest to the bedroom and it should be plenty for sleeping. Which state park? Nights are still cold for us in May, even when the days are warm.

There are also these, which may or may not help depending on how your power distribution is.

https://www.amazon.com/BLACKHORSE-RA.../dp/B08DQYLPYY

[Old Scout]

Two AC's on 30 amps--sorry, usually not, even with lots of "planning".....

[cavie]

Originally Posted by Dr. Dolittle

I'm trying to make reservations for mid May at a nearby state park that my wife wants to visit. All of the dates I've tried show only 2 sites available, both showing 30 amp service. I'll be parking a TT with 50 amp rating, dual air conditioners.

If we're careful with other electrical loads could we run both A/C units? Is there a CB to pull or some other way to only run one A/C unit?

We don't have the TT yet or I'd look for the CB solution myself. Also, it might not be hot enough at night that time of year to even need the A/C but I'm trying to plan for all possibilities.

First thing you will need is a 30/50 dogbone. Just leave 1 A/C off.

[BillJinOR]

Each ac in most Rv's is independently controlled Via the Thermostat or Thermostats so you can easily use just one. For Most 50 amp RV's only one can be run as already explained.
A 30 amp site is limited and on a power hungry 50 amp RV requires you to just not run things at once. Keep in Mind your water Heater may have an electric element, If the Refrigerator is gas (which on auto senses power and uses an electric element instead of gas that draws a lot of energy) or residential electric. Not to mention the battery charger that can draw amps if the batteries are low. 30 amps happens fast! A 30 amp site has 30 amps a 50 amp site has two 50 amp feeds (100 amps total) ea powering 1/2 or your rv.

[Dr. Dolittle]

Originally Posted by jrollf

Run both on 30 amps... It 'depends'...

How large are the AC units? If they are two 15k BTU units it may not or may not be possible.

They're each 13.5 BTU.

Originally Posted by cavie

First thing you will need is a 30/50 dogbone. Just leave 1 A/C off.

What is a dogbone? Can you provide a link?

[SKP Kirk]

While each air conditioner will have it's own circuit breaker, there is no need to turn it off you just do not turn on but one air conditioner at a time. You probably can operate both of them when little else is in operation as most air conditioners will draw about 8 - 10A when in good condition, but you will need to turn one off to use the kitchen.

In order to connect your 50A power cord to the 30A outlet you will need one of these adapters.

[SailorSam]

Putting an Easy Start on both AC units will make it more likely that you can get both units running on 30 amps. Because the reduce the startup stress, they may extend the life of the units. Do a search on these on RV chat sites and you'll find lots of people use them. I've seen posts of folks who do run 2 ACs with them on 30 ampsWith an Easy Start you can probably run 1 AC on a 2200 watt generator.
https://www.microair.net/collections...-soft-starters


Using the dogbone that NewBlackDak recommended will work if the 15 and 30 amp connections are on separate circuits. Otherwise, you run the risk of overloading the wiring. Pedestal may be setup for a 30 amp max.

[wolfe10]

Keep in mind what power is available:


30 amp provides 30 amps


50 amps provides TWO 50 amp hots= 100 amps total power available.

[boomersooner]

Might also want to consider turning off AC when you need to run microwave. When microwave is done that turn AC back on.

[Persistent]

All good advice above.

The math is relatively simple. You can work in watts, or you can work in amps.

The A/C's may each draw 13 amps while the compressors are running.
13 + 13 = 26 amps.
However, when a compressor starts it may draw twice that. Most AC circuit breakers allow for that. Starting two at once will likely trip the breaker.

A microwave can also draw 13 amps or so. They generally don't spike such a high starting load.

13 + 13 + 13 = 39 amps. The circuit breaker will trip.

An electric water heater will draw 13 amps when the thermostat switches "on".

A big battery charger can draw significant AC current. However, you cannot just add the 12 volt charging current to the total. A 100 amp battery charger may draw 11 amps at 120 volts AC. A 50 amp charger may draw 6 amps at 120 volts AC.

When batteries are fully charged, the battery charger will draw very little AC current.

So turn on no more than two high current items at a time. Start one A/C and wait 5 minutes before starting the second one. If batteries are low, charge them for 4 hours or more before starting the second A/C.

The worst that can happen is the pedestal circuit breaker will trip. Then turn things "off" and reset the breaker.

Note: A few campgrounds have circuit breakers located in a central panel. It can be inconvenient to get a service person to reset the breaker.

I wish you good luck and happy trails ahead!

[Old-Biscuit]

30A...get/use the 50A to 30A Dogbone adapter (posted above)
Run fridge/water heater on Propane
Run only 1 A/C Unit...swap at night time (IF it is even Hot enough in MAY to need A/C)
**no need to open any CBs....just leave A/C off via it's thermostat

Don't overthink it.......go have FUN

[twinboat]

The adaptor that " NewBlackDak " suggested will not work with a GFCI outlet. Says it right on the packaging.

Just about every standard outlet is GFCI protected, don't waste your money.