Can I run a 220 volt welder off batteries?

[Krash]

Hello, first post here. I didn’t know if I should post this on a welding forum or here, but I figured one of you may have done this before.

I just bought a trailer to tow behind my motorhome to take my car with me on extended trips. Actually, we will be full-timing in the motorhome soon, so I will be adding a 600 watt (approximately) solar system to the trailer, as we plan to be off grid most of the time.

The trailer will also be used as my workshop too. I do some wood working and some welding also.

Although the motorhome has a generator, unfortunately it won’t produce 220 volts to run my mig welder.
What I am trying to find out is if it is possible, and practical, to try to run my welder from my 12 volt solar battery bank. Here are the welder’s specifications:

Rated Electrical Input: 210-240 VAC; 50-60Hz; 22AMP
Max Voltage at No Load: 20 V DC
Rated Duty Cycle: 130A@30% duty cycle

Now, I am not some great welder, in fact, I barely get the job done, so all of my welding is on small projects, and I would never be welding for more than 10-20 seconds at a time. And I don’t care if I only weld 1 minute out of an hour. In other words, I will never approach my welder’s duty cycle.

None of the solar equipment has been decided on yet, but I am expecting to have 4-6, 6 volt Trojan batteries wired in series-parallel. I want to keep the whole system at 12 volts because of the motorhome. I will be using an appropriately sized MPPT controller, and have not decided on the inverter yet because of this 220 volt welder question.

Oh, one other thing, when using the welder, there would be no other draw on the battery bank. I would be welding so seldom that I can shut off all the other draws on the system.

So, can anyone tell me if this can easily be done?
Thanks

[Sunking]

It could be done if money is no object and you have a trailer to hold all the batteries and panels required. That is why portable welders have big gas or diesel engines.

[Living Large]

{snip}
Here are the welder’s specifications:

Rated Electrical Input: 210-240 VAC; 50-60Hz; 22AMP
Max Voltage at No Load: 20 V DC
Rated Duty Cycle: 130A@30% duty cycle

{snip}

None of the solar equipment has been decided on yet, but I am expecting to have 4-6, 6 volt Trojan batteries wired in series-parallel. I want to keep the whole system at 12 volts because of the motorhome. I will be using an appropriately sized MPPT controller, and have not decided on the inverter yet because of this 220 volt welder question.

{snip}

Let's say the welder takes 4840W. At 4 batteries, that's 2 x 2. 4840/12 = 403A, divided by two, or 201.5A through each string.
If you have 6 batteries, 3 x 2, 134A through each string. That's a lot of current. My guess is there is no way. I am new to this, but I believe you would need a (large) 48V system. Or run the welder on a generator?

[Mike90250]

On a 12V system, not a chance you will be able to power a respectable welder.

You are better off hooking 4, 6V batteries in series, and using them with a Stick Welder handle & electrode. It may take a while to recharge the batteries. And you better KNOW how to weld, because if you get the stick stuck ...

[Willy T]

These work just fine on 2, 12 v batteries. I'v seen them used 100's of times on boats in the water. While not a production welder they will work.

http://www.goweld.com/prodinfo.html

[Sunking]

These work just fine on 2, 12 v batteries. I'v seen them used 100's of times on boats in the water. While not a production welder they will work.

http://www.goweld.com/prodinfo.html

200 amps @ 42 volts.

[Willy T]

200 amps @ 42 volts.

Not what I read, 24 or 36V, I'v always seen them used with 2, 12v batteries. Again not for production , but they will work on small projects. Where I have seen them used on aluminum boat hulls for in the water repairs.

http://www.goweld.com/batteryselection.html

ScreenHunter_927.jpg

[Krash]

Just to clarify, I will be welding very small projects, all aluminum. I think most trade welders would consider what I will be doing as “tacking”. Maybe three welds in an hour, and no weld would be over two inches in length. The material is 1/8 aluminum only.

I am not talking about doing any heavy welding of structural materials. I think I can get the 220 volts needed by stacking inverters, and then test my welder. If I have any problems, I think I can just add another stack, can’t I?

[Sunking]

Not what I read, 24 or 36V, I'v always seen them used with 2, 12v batteries. Again not for production , but they will work on small projects. Where I have seen them used on aluminum boat hulls for in the water repairs.

http://www.goweld.com/batteryselection.html

[ATTACH=CONFIG]5376[/ATTACH]

200 amps on a 50 AH battery is not doable. Specs clearly state 200 amps @ 42 volts.

[SunEagle]

200 amps on a 50 AH battery is not doable. Specs clearly state 200 amps @ 42 volts.

Yeah it "clearly" states - "Rated input = 200amps, 42VDC (two or three 12 volt batteries)"

Not sure if that 24VDC and 200Amp listed are maximum input limits. I also can't see how you can get 2 or 3 12v batteries to equal 42V

[thastinger]

Just to clarify, I will be welding very small projects, all aluminum. I think most trade welders would consider what I will be doing as “tacking”. Maybe three welds in an hour, and no weld would be over two inches in length. The material is 1/8 aluminum only.

I am not talking about doing any heavy welding of structural materials. I think I can get the 220 volts needed by stacking inverters, and then test my welder. If I have any problems, I think I can just add another stack, can’t I?

Sooo you'll be going with a Miller EconoTIG at a min I suppose? Do you plan to preheat the alum? If not, you'll need to consider the power consumed while you have the pedal fully depressed (assuming that is even possible with you planned setup) attempting to get the alum to operating temp. If you do happen to do it, I think you'll find yourself welding differently from battery than grid power.

[Krash]

Nope, MIG not TIG. I clearly misled everyone with my post title. I will try to explain.

I have a Eastwood 175 mig welder with a spool gun that I use on small aluminum projects. This runs on 220v AC. On any given day, I only actually weld for 5-10 mins over the course of the whole day. I mean actually striking and arc, and welding. I weld in 5-10 second burst a few times spread oven an hour.

I am talking really low usage on very small material, never over 1/8 inch think. My beads are never more than two inches in length.

My welder is powered by 220 volt AC current, not DC. I want to know what type of inverter can be used from my 12 volt solar charged battery bank to run my welder, if it is even possible.

Sorry that I misled some of you to thinking I wanted to run directly of DC power.

[thastinger]

So that welder draws 22A @ 240V. I'm not aware of any inverters that are going to have a direct plug in for the welder but I suppose you could hard wire the inverter to a dryer style boxed in outlet and get it to work like that.

That will require a 5280W inverter capable of kicking up to 7K for a few seconds for the welder initial arc.
In no way am I recommending this inverter because I know nothing of the brand reliability but the specs look like they could work for you

http://www.amazon.com/Power-PICOGLF40W12V230VS-4000W-Inverter-Charger/dp/B00JJ8UDG0/ref=sr_1_17?ie=UTF8&qid=1418784999&sr=8-17&keywords=240v+inverter&pebp=1418785134630#productDetails

What size is you battery bank again?

[Krash]

Yes, I have been looking at the Aims units. They seem to be the type I would need with the split configuration, but in reading about them, everyone seems to think they are junk. I just got finished reading several post.

Recommendation seem to be toward one like the Magnum found here. http://www.solar-electric.com/maenms4444wa.html
But it is more than twice the price. Which I don't mind if I could be sure it would work. It would certainly be overkill for the rest of my needs, but that is fine too.

I haven't decided on batteries yet, but I don't expect them to be much of an issue as far as having 4 to 8. Although how I configure them might have some effect. I am hoping to keep it at 12 volts, but can do 24 volt also. I will probably go with Trojan 6 volt batteries, but not 100% sure yet.

[Sunking]

My welder is powered by 220 volt AC current, not DC. I want to know what type of inverter can be used from my 12 volt solar charged battery bank to run my welder, if it is even possible.

OK here is the problem. You would need a 8000 to 10,000 watt inverter, and there is no such thing as a 12 volt 8000 watt inverter. At that wattage would require a minimum 48 volt inverter. But lets pretend you could find a 12 volt 8000 watt inverter. The 12 volt DC current would be 750 amps. FLA batteries can only be discharge at about C/8 which means you would need 12 volt 6000 AH, 4400 pound, $14,000 battery. The solar required to charge such a large boat anchor would be 8000 yo 1000 watts.

Only economical and practical way to do this is with a portable welder on a trailer that uses either a gas or diesel engine. Something on the order of a 20 hp engine turning a 12 Kva generator.