My portable AC keeps tripping the breaker

bondebond

Super Active Member
Aug 14, 2008
2,330
Then focus troubleshooting issues on the generator.

If the AC works plugged into good power, then it's probably not the AC.

Plug an electric heater or hair dryer into the generator. Those are usually around and up to 1500 watts. But they have no goofy electronics in them.

If it trips on a hair dryer, then maybe that "120/240 or 120" set to 120/240 is the wrong setting, or you have a bad generator. It's pretty straight forward IMO.
 

Jkoht

Active Member
Aug 10, 2020
164
Why are you trying to run it with the switch in the 240v mode? That clearly isn't right push that switch to 120v only.
 

Ladiesman

Super Active Member
Feb 6, 2018
840
Does the AC work when plugged in to 110?
Yes. It didn't have a problem at all when we used it a month ago on shore electricity at campsite.p
Why are you trying to run it with the switch in the 240v mode? That clearly isn't right push that switch to 120v only.
I think you nailed it. Flip the switch to 120V. The 240/120 is for when running 240/120 at the same time. Meaning something in the 120 volt and actually having a 240 piece of equipment plugged in to the 240 outlet. The way its set now you are not balancing the load causing the generator to freak out. That generator is more than capable of powering your pup and AC. I have one about the same size and plugged my pup with AC in and then after my pup the TT and it was more than able to handle it.
 
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ChiefHart

Member
Apr 2, 2020
78
Staunton, Virginia
Yes and it still trips the breaker. Just bought the generator June 5th. The AC works if I plug it into my house. It just keeps tripping main breaker on the generator.
For all responding to this problem. I read that one of you talked about a floating Neutral. I noticed on the generator a post for a ground. QUESTION shouldn't this generator in this application have an earth ground? That might be the cause of a Floating Neutral and a possible problem with the AC tripping the Breaker.
 

tcrawford07

Member
Jun 26, 2022
14
Northeast Texas
Then focus troubleshooting issues on the generator.

If the AC works plugged into good power, then it's probably not the AC.

Plug an electric heater or hair dryer into the generator. Those are usually around and up to 1500 watts. But they have no goofy electronics in them.

If it trips on a hair dryer, then maybe that "120/240 or 120" set to 120/240 is the wrong setting, or you have a bad generator. It's pretty straight forward IMO.
I think you're on to something. I'll plug in my single cup coffee maker. That little thing is 1000 watts. I'll see if it trips it.
 

NLB

Active Member
Silver Supporting Member
Oct 10, 2021
501
West Palm Beach, Florida
For all responding to this problem. I read that one of you talked about a floating Neutral. I noticed on the generator a post for a ground. QUESTION shouldn't this generator in this application have an earth ground? That might be the cause of a Floating Neutral and a possible problem with the AC tripping the Breaker.
The floating neutral is a design feature. The only way I know to solve it is with a bonding plug. It it a very common problem with non-RV generators being used in an RV setup. Tons of info available both on the internet and customer reviews for the products where they are sold.
When I bought a generator I questioned on this forum about using an earth ground, and was booed off the stage. Still think it’s better than 3kw traveling from my hand to my feet, but the consensus is don’t bother with it Sparky. 🤷‍♂️
 
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ChiefHart

Member
Apr 2, 2020
78
Staunton, Virginia
More info from the AC instruction manual. Unit has to be connected to a 120-V 15-A GROUNDED circuit with a time delay fuse or a circuit breaker, and must not be on an extension cord. That is on page 3 of the manual.

Maybe there is a voltage drop with the extension cord or the AC electronics senses the unit is not grounded and sets a fault ( trips breaker) on your generator. The breaker on you generator may be more sensitive than a home service panel breaker, so you are getting trips on the generator.
 

tcrawford07

Member
Jun 26, 2022
14
Northeast Texas
Well y'all, we figured it out. Hubby had it plugged into the BIG plug. We switched it over to 120v like someone said, and plugged it into the 20v outlet and wallah! The AC ran just fine with little pull on the generator. Turned the fan on, no difference at all and then the lamp. No change. 😁 Thank you all so much for your help. I won't use an electric coffee maker. I have a stove top percolator. Which is my camp pot anyway. But the real test will be, plugging up the ice maker and the fridge we have. It should carry those too, don't y'all think?
 

ChiefHart

Member
Apr 2, 2020
78
Staunton, Virginia
The floating neutral is a design feature. The only way I know to solve it is with a bonding plug. It it a very common problem with non-RV generators being used in an RV setup. Tons of info available both on the internet and customer reviews for the products where they are sold.
When I bought a generator I questioned on this forum about using an earth ground, and was booed off the stage. Still think it’s better than 3kw traveling from my hand to my feet, but the consensus is don’t bother with it Sparky. 🤷‍♂️
Grounding the generator must not be important, because they put that instruction in the generator instruction manual (sarc). Grounding to earth will protect against a fault in the 120-V load device that could keep the generator it self from becoming electrically HOT. Touch the energized generator chassis and be in contact with the wet ground and that could equal DEATH. I am sorry the forum Booed you on a real safety procedure. In the Navy every electrical device has to be grounded and checked periodically. Navy Safety Regulations are always written in blood.
 

NLB

Active Member
Silver Supporting Member
Oct 10, 2021
501
West Palm Beach, Florida
Thanks for your service Shipmate. You needn’t apologize, and I am fully aware of the safety issues involved.
My reading of the electrical code requirement is that an 8 foot copper rod be driven into the ground so I doubt I will comply to that degree.
I suspect that the reason my generator exterior is totally plastic is to help keep me safer. I will utilize the ground lug to provide a path for any stray electrons to find their way home, and keep my mitts off energized circuitry.
The OP has an open frame unit and that presents additional opportunities to light up the night sky, so you are right to voice your concerns.
Whenever I am offering advice, I am always concerned about the skill set of the person inquiring. Especially when any safety issues are involved, and I try to point out possible areas of “danger “.
I survived countless hours on a flight deck and years in the aviation industry. My credo is “There are old pilots, and bold pilots. But there are no old, bold pilots”. Fair winds, and following seas to you, Chief.
 

NLB

Active Member
Silver Supporting Member
Oct 10, 2021
501
West Palm Beach, Florida
Well y'all, we figured it out. Hubby had it plugged into the BIG plug. We switched it over to 120v like someone said, and plugged it into the 20v outlet and wallah! The AC ran just fine with little pull on the generator. Turned the fan on, no difference at all and then the lamp. No change. 😁 Thank you all so much for your help. I won't use an electric coffee maker. I have a stove top percolator. Which is my camp pot anyway. But the real test will be, plugging up the ice maker and the fridge we have. It should carry those too, don't y'all think?
It will. That Genny is a powerful beast. Happy Trails!
 

George Dion

Member
Jan 29, 2020
14
Illinois
To better understand, You have the pup plugged into the 30 amp outlet and the air conditioner plugged into the pup and when the compressor kicks on it pops the breaker on the generator? If you are only using the regular GFCI outlet on the generator to power everything and not the 30 amp which you need an adapter from 4 prong twist lock to 30 amp RV then its tripping due to pulling to much amperage. The regular outlet will be 20 amps. That AC just a guess probably pulls 12 amps. Now the pup added in converter running when the compressor kicks on you have over loaded the 20 amp circut.
Breakers are designed to trip at 80% of rated value. 20 amp breaker will trip at 16 amps of load.
 

stierheim

Member
Apr 22, 2013
57
Breakers are designed to trip at 80% of rated value. 20 amp breaker will trip at 16 amps of load.
This is incorrect. Breakers are designed to trip above the rated load. The UL (Underwriters Laboratory) requirement for breaker certification requires the breaker handle 100% of its rated load indefinitely when operated in open air. In an enclosed very hot environment, it is possible for a breaker to trip as somewhat below its rated load.

I suspect you are confusing a NEC (National Electrical Code) requirement that a breaker be sized at 125% of its load (which is 80% of the breakers rating, hence the 80% rule). Note the rule does not change the breaker's rating itself, it requires the breaker's nameplate trip rating to be 125% of the load. However this NEC requirement is only imposed if the load is a continuous 100% load for 3 or more hours. This type of load does not occur in the RV or residential environment and the 80% sizing rule therefore does not apply.

Note however, that the 80% sizing rule does not ever impact the breaker rating itself. A working breaker will always handle its rated load for an indefinitely amount of time as long as it is not in an extremely hot environment.
 




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