Inverter, will it work?

Ray LeTourneau

Senior Member - Past Moderator
I have a 1 horse 120 volt compressor rated at 10.5 amps. It's a direct drive but uses oil for what that's worth. My question is can I use an inverter if necessary to power it for a short time and if so, how big? I was thinking 2000 watts. I didn't buy a 12v compressor because we are mostly hooked up to electric but there are a couple times I have needed air and not had elec available. Thanks.
 

Pulltab

Well-known member
I don't know if it will start it or not for sure Ray, but my guess is that it will not. The starting load will be so great it may pop the breaker. The 10.5 amps would not be a problem but the starting current may be 20+ amps. Hopefully someone will chime in with your answer
 
At 120Vac, the inverter must be able to supply 1260W to run the compressor. However, as in the previous post, the startup current will be about 20amps. Therefore, you will need an inverter that can handle about 2400W initially or until the compressor is up and running.

Voltage times current = power in watts.
 

vangoes

Well-known member
Ray,
I bought a Sears 120v portable compressor and use it with a 400W inverter and it works great. The compressor pulls 3.3 amps and the small inverter handles it with no problems.
Craftsman 120 volt Air Compressor Inflator

Sears item #02875117000 Mfr. model #75117Craftsman 120 volt Air
 

Forrest Fetherolf

Senior Member
Ray L,

To size inverters, Volts x Amps = Watt. 120 Volts x 10.5 Amps = 1260 Watts. A 1500 watt inverter will work. Harbor Freight has the 1500 watt for $90.00 and a 2000 watt for $150.00 either with a 15% discount. I bought the 2000 watt, mounted it on top of the Onan with #4 battery cables from the double 12 volt batteries.

Forrest
 

Attachments

  • Inverter001.JPG
    Inverter001.JPG
    160.7 KB · Views: 44

Pulltab

Well-known member
Forrest, you think it can handle the starting amps? I realize the running amps is no problem. I did a quick search and starting loads can be 3-6 times running current.
 

Pulltab

Well-known member
vangoes said:
Ray,
I bought a Sears 120v portable compressor and use it with a 400W inverter and it works great. The compressor pulls 3.3 amps and the small inverter handles it with no problems.
Craftsman 120 volt Air Compressor Inflator

Sears item #02875117000 Mfr. model #75117Craftsman 120 volt Air

I also bought a sears compressor that pumps up to 140 psi. Works great and is fairly compact.
 

Forrest Fetherolf

Senior Member
Pulltab,

I run a Porter Cable 10 amp compressor with 150 lb cut-off...........no problem. The 2000 watt inverter is rated for 4000 watt surge.

Forrest
 

chardel

Active Member
I have been wondering about installing an inverter and where to put it and a couple of more batterys to make it run as the big horn we are picking up next week only has 1 battery. I see from Forrest's pic that it must be in the front compartment? I had been concerned that the inverter might need to be in one compartment and the batterys in another and how all that might need to be tied together to make it work. Also had wondered if the standard charger that comes with it would handle additional batterys or would any add-on inverter need to be one of the inverter/charger models? From Forrest's pic, it looks like you have two additonal batterys to power the inverter - is that correct? Would like to be able to power tv's, lights, water pump, slides and the air compressor for an evening or so if not hooked to shore power with an inverter system without getting overly elaborate on the system install.
 

Ray LeTourneau

Senior Member - Past Moderator
Thanks for all the help! I think 4000 will do nicely. I have to wonder though, Forrest, why have an inverter if you have a generator? Overkill? Just in case?
 

Uncle Rog

Well-known member
chardel ,here is the unit I have, http://www.xantrex.com/web/id/49/p/155/pt/24/product.asp
Xantrex sells them refurbished also for about half price. Make sure that you can live with the modified sine wave first. I like the 100a charger for the 450a battery bank and the 160a reserve. The only things you will need the inverter for are 110v systems, lights, pump etc are all 12v. Good luck........
 

Forrest Fetherolf

Senior Member
Ray LeTourneau said:
Thanks for all the help! I think 4000 will do nicely. I have to wonder though, Forrest, why have an inverter if you have a generator? Overkill? Just in case?

Ray L,

This is both "just in case" and "over kill", I can inflate the truck air bags, Trail Air hitch pin, and adjust tire pressure without starting the Onan or connect to shore power.

I have always been a gadget guy and I had that space available on the Onan.........................had to put something there!!!!! ;)

Forrest
 

Pulltab

Well-known member
Chardel, Rog is right on with the Xantrex inverter/charger. It's a very good unit. I have 6) 6volt batteries in the front bay and have the inverter installed in the basement behind the wall where the factory converter is. I ran heavy cables to the batteries thru the underbelly. The Xantrex charger works so much better than the converter charger. If you buy the Xantrex also get the remote panel to turn it on and off and that panel has a power share function so you can control how much of your incoming power is dedicated to charging.
 
Top