DC Welders

Been looking for a welder/generator for awhile- Craiglist has a 200 amp Onan with engine for $450- I know DC is tops for welding, but what kind of household stuff can you run on 110 V DC? Freezer and Refrigerator? Lights?

He says it generates 3500 watts "at idle"- would it be feasible to put an inverter on for AC? I've seen them on pickups, but could you get one (reasonably) for 3500 watts?

Is John T., AKA "Sparky", still horsing around in sunny Florida? We need him back on the board. . .

Don't try anything on 120V DC except incandescent lamps and electric motors with brushes such as drills and circular saws.......if. If they don't have a variable speed control.
In all honesty you will save nothing trying to "make do".
If this is a engine powered welder. There is likely the main welding leads. And a separate circuit with a pair of 120V U-Ground AC 15amp receptacles.
Should work ok. It will burn for fuel than a dedicated 3500W portable generator. Only a concern if power is out for days.

Double check to make sure it doesn't put out AC. I know the Lincoln welder I have that has a 2 cylinder Onan engine has an outlet on it which is 15 amps but it is DC only so that limits what you can use like drills and grinders and light and that is about it

No, its strictly DC. It wouldn't run a refrigerator or freezer motor? That's about all we need during power outages, and really have no other use for it as a generator.

120 DC will only run brush motors. Got to have AC for induction motors such as in a refer or freezer.

I have a Miller Roughneck and it puts out 115 vac. I have not used it to run household appliances, but I think I will give it a try just to see what it will run. I should at least be able to keep the fridge and freezer going with it.

I have a Roughneck. Power down for 3 days. It ran...furnace, lights, tv, frig and some other stuff. The Miller puts out 30 amps....add it up...100w light bulb..1amp fridge about 8..The miller had no problem. I did run two 50'extension cords as feed lines. It just happily buzzed along.....hour after hour after hour.

120V DC supplied into an AC induction motor such as your fridge,freezer, sump pump etc. It will make a bad smell while letting the electricity leak from the wires.
You will be happier with a 8-10,000W generator to run your house. And you can plug an ordinary AC/DC welder into it and weld all day.

"what kind of household stuff can you run on 110 V DC?" Incandescent lights, radiant heaters without blower motors, 110 volt electric stove elements...that's about it. Resistive loads and motors with brushes generally don't care; anything with a power supply, electronic controls, induction motors, flourescent lights, etc., requires AC.

At one time there were household appliances available that would run on 110 AC or DC, but they pretty much went by the wayside with the completion of rural electrification in the 1940's & 50's.

The typical consumer type inverter requires 12 volt DC input, not 110 volt DC. They're designed to run off a vehicle power supply. There are inverters avaialable with 24 or 48 volt inputs for solar power systems, but I suspect they'd cost more than a stand alone generator of equivalent capacity. I've never heard of an inverter with 110 VDC input, which means if they are avaialable they'd be a specialty item and therefore expensive....

A household refrigerator would probably require an inverter with a starting (surge) capacity of at least 1500 watts. I wouldn't even consider trying to run one that large off an automobile for more than a very short period of time, and then only off the battery unless you have a very large capacity alternator.

If cost is the primary driver, your best bet may be a used generator for backup power, and then buy whatever you need for a welder. Around here (Colorado) you see older generators on craigslist for a couple hundred dollars all the time, and some for a lot less than that if you're willing to work on them. I got an older Sears 1800 watt electric start unit for $20 off of craigslist, needed a new head gasket and the carburetor cleaned to run perfectly.

Keith

120 DC will run the lights until you turn off the switch. It will arc over and not turn off. Then the switch is shot & won't work on AC either.

What brand of welder is it?
My old Onan driven AC DC Miller welder puts out 3.5kw AC if you throw the knife switch to the 110 setting