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50 amp to 30 amp?

Creek Jenkins

Well-known member
Alliance advertises that you can run two air conditioners on 30 amp so does that mean you can use a 50 amp to 30 amp adapter? If so, one leg would be not powered (I assume) so what circuits would be not energized? My dual generator setup only has a 30 amp plug.
Cheers
Creek
 

BryanValRox

Well-known member
Alliance advertises that you can run two air conditioners on 30 amp so does that mean you can use a 50 amp to 30 amp adapter? If so, one leg would be not powered (I assume) so what circuits would be not energized? My dual generator setup only has a 30 amp plug.
Cheers
Creek
Think of it this way, 30 amp to 50 amp. The adapter would have an internal jumper to power both legs.
Both legs remain powered, but obviously your available amperage is limited
 

BryanValRox

Well-known member
I don’t think it works that way, aren’t the two legs 180 degrees out of phase?
Cheers
Creek
The adapters do work as I have described.
I have a 15 amp to 30 amp, a 15 amp to 50 amp, and a 30 amp to 50 amp, both legs are always maintained on my adapters.
Grab your VOM and check it out for yourself.
Looks like you might be used to working some High Voltage Multi phases systems based on your profile picture. How many tons can that one handle?
 

Creek Jenkins

Well-known member
Crap I was thinking of a regular 240 volt house connection but nothing runs on 240 in a camper so no reason the two legs can’t be connected. Sorry about that. Have you ever run two ACs on a 30 amp circuit? I really don’t want to buy a new generator.
The truck in my avatar is a Belaz 75710, unit #2, one of only four made. If you look close you can see unit #3 and #4 in the background. I’m standing by the front tire. Largest surface haul truck in the world, 450 metric/ 500 short tons capacity. I’d bet a few cases of beer all four of them are parked at a mine somewhere in Russia due to lack of spares. They used Western engines (MTU) and drive trains (Wabtec).
Thanks for setting me straight on this, I won’t be able to test out the AC until the weather warms.
Cheers
Creek
 

BryanValRox

Well-known member
Crap I was thinking of a regular 240 volt house connection but nothing runs on 240 in a camper so no reason the two legs can’t be connected. Sorry about that. Have you ever run two ACs on a 30 amp circuit? I really don’t want to buy a new generator.
The truck in my avatar is a Belaz 75710, unit #2, one of only four made. If you look close you can see unit #3 and #4 in the background. I’m standing by the front tire. Largest surface haul truck in the world, 450 metric/ 500 short tons capacity. I’d bet a few cases of beer all four of them are parked at a mine somewhere in Russia due to lack of spares. They used Western engines (MTU) and drive trains (Wabtec).
Thanks for setting me straight on this, I won’t be able to test out the AC until the weather warms.
Cheers
Creek
No worries at all, this kind of discussion is what makes the knowledge sharing on this forum valuable.
We all learn about various topics that get posted here and use everyone’s comments to sharpen our saw!
The collective knowledge on this forum is extremely valuable to all of the Allies!
Two AC units can be run off of 30 amps(soft starts will need to be installed on the AC’s to reduce the in rush to the compressor to ensure reliable operation on the generator or shore power pedestal (preventing breaker tripping). For example, our AC’s LRA is 54 amps and our RLA is 9 amps.
We are normally hooked to 50 amp shore power when we camp so I have no direct experience running 2 AC’s on 30 amps. Many on this forum do this regularly.
 

Oregon_Camper

Forum Admin
Staff member
Is this just you thinking about using RV park with 30 amp, or do you use a lot of RV parks with 30 amp service? If you know you're going to do that a lot, I'd recommend adding a Victron MultiPlus II. Once installed, it can detect your incoming power (30 amp) and if the RV needs more power than shore can provide, it will use the "inverter" function and provide 50 amps, using battery power. Then when you get to spot where both AC units are no longer needed, it will flip over to "converter" mode and recharge battery bank....all with you not having to lift a finger.

I have this our 340RL and never worry about using 2...or even 3 AC units.
 

Creek Jenkins

Well-known member
We boondock a fair bit, so I’m sure I will have a chance to test it. When Alliance advertised the dual ACs on 30 amps I was hoping it was because they already installed soft starts. I’ve got dual Honda EU2000 gens running in parallel so it wouldn’t be the end of the world to upgrade to a single 4500 or 5500 generator if I have to.
You are right this forum is a great resource, I’m just very disappointed in the lack of information in the owners manual. Most of this stuff should be in there. The only way I can find how to operate my waste valves, what my disconnects are for, how the gas tank regulator/ switchover works, etc. is to ask on this forum. That’s not good.
Cheers
Creek
 

Creek Jenkins

Well-known member
The Victron sounds like a good idea but I’m still living in the lead acid world. Lithium I’m sure will happen in the future. When we are on shore power we usually have 50 amp so no worries. It’s the boondocking I’m worried about.
Cheers
Creek
 

Bozo

Well-known member
I can tell you that I frequently camp in places with 30A service and run 2 a/c no problems. I did this before soft starts for 1st year and added soft starts 2nd year as a “safety” measure. You would want to limit any heating type appliance use if both a/c are running though. I usually put my coffee pot out on a table and run that off the pedestal separately under those conditions.
 

Lantley

Well-known member
I do believe it's possible to run 2 AC units on 30 amp, however I would caution you to monitor the voltages going to the units.
They will run and sound fine but the incoming voltage may drop to harmful levels. If you are running 2 AC's on a 30 amp circuit be sure you know what voltages your units are running at
 

Oregon_Camper

Forum Admin
Staff member
I can tell you that I frequently camp in places with 30A service and run 2 a/c no problems. I did this before soft starts for 1st year and added soft starts 2nd year as a “safety” measure. You would want to limit any heating type appliance use if both a/c are running though. I usually put my coffee pot out on a table and run that off the pedestal separately under those conditions.
Yikes.. Where do you camp where you have to run 2 AC units at 6am? I don't want to go there.... 😂😂
 

Bozo

Well-known member
Yikes.. Where do you camp where you have to run 2 AC units at 6am? I don't want to go there.... 😂😂
When the corn is sweatin’…..not necessarily at 6 a.m. but midday. Mid august and sept. in iowa usually. I do alternate back and forth On units. I spend most time outside but I like it cool when I sleep.
 

Creek Jenkins

Well-known member
I did a VOM check as you suggested just for my own curiosity. Bryan is correct the two hot legs are connected. So when Alliance advertises that you can run two ACs on 30 amps is it because they have them on 15 amp breakers?
 

BryanValRox

Well-known member
I did a VOM check as you suggested just for my own curiosity. Bryan is correct the two hot legs are connected. So when Alliance advertises that you can run two ACs on 30 amps is it because they have them on 15 amp breakers?
So my take is that they can state that because of the RLA is below 15 amps on each unit while it is in operation.
You will need soft starts to prevent tripping breaks at start up due to the LRA at compressor start on 30 amps for reliable operation.
 
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