Extension cord for 220V?

[thcri]

RaT and Inspector,

This is interesting and I believe you are right. It is interesting though that I have a 4 wire in my garage?? I know that inspectors have the right to strengthen codes and being a HVAC/Plumbing Contractor I did pick one of the best electricians that I know of in town. When it was put in I never questioned it and didn't even realise it until I went to hook up my two dryers. My existing dryer that I brought from my old house I had to change, the new dryer already had the 4 prong on it. I will have to ask my electrician about it. I will report back when I get the information.

murph

 

[JATO_RaT]

You would be better off having the 4th wire there and not utilize it then to have a 3 wire and need 4. I think the electrcian was doing it correctly. It could be changed to a 3 prong receptacle should it be used for a 240V only device ignoring the neutral or white wire. You are correct though, for the dryer you will indeed need it to be 4 wire.

 

[Gary_in_Indiana]

My outlet nearest the outside is already about 75' from the box. Any problem running additional distance beyond that using an extension cord?

 

[JATO_RaT]

Thats a question you can't answer until the amperage or current draw is known of the given device. If you have a volt meter, especially a digital one, try checking the voltage with no load at the outlet and then again under full load. You should not have much more then about 3% drop in voltage although for a stick welder, this value will be less critical.

 

[Gary_in_Indiana]

The welder in question is a Hobart 175 MIG unit. According to Hobart the Max Open Circuit Voltage is 30 V. Does that give you what you needed?

 

[wroughtn_harv]

Gary I have three such extension cords. Two of them are now currenty in use on the project I refer to in "lofty goals" over in Photos.

You can buy male and female plugs at your local box store. You can also buy, find, appropriate appropriately otherwise eight--three or six--three cord.

At the project I wired up the meter panel and the local power company supplied two hundred amp service. For my welding I use two hundred and fifty foot leads on spools made from wheels attached to trailer. I have short cables to pick up these leads to the truck's two hundred and fifty amp Trailblazer from Miller.

On hand I have the acetyline torch, sawsalls, portaband saws, cutting blades on grinders etc. But sometimes the best dawg to hunt with when cutting steel is a simple old plasma torch. For this I have direct wired one of the welder extension cords to the breaker. I have the other cord plugged into it and then the plasma can be used anywhere anytime. That's a good thing.

Air for the plasma, now that comes from a Sullair 185 diesel sitting back of the barn. I've made a sheeps foot adaptor to a standard quarter inch quick connector. I put in an extra dryer in line because the air from the compressor is a tad more than damp.

For you purposes I think I'd consider making a couple of cords. One of them I'd do a little longer than the other but the total footage would meet your longest need. These cords are big and heavy. Handling them is a hassle. Having one not too long will work great when you need to take the welder to the rear of a trailer already hooked up to the truck. Having one a little longer will work when that one just doesn't reach. And on those occasions when you absolutely need some footage the combination will be slicker than grass exiting the goose.

At the shop some of my equipment is off all by itself. The two twenty stuff has welder plugs on them. So like when I need to use the power hammer I unroll the shorter cord and we're in business. The same thing goes for the spa blower that has been to school and graduated as a genuine air supply for the sand blasting hood. It still makes the same gawd awful racket that it did making bubbles in the spa. But it stands a little taller I swear. I think it has to do something with doing honest work. /forums/images/graemlins/grin.gif

 

[JATO_RaT]

Amps Gary amps /forums/images/graemlins/laugh.gif A 175 amp MIG unit should work just fine on a #10 extension cord. I suggest making no longer then 50' cords, even #10 gets awkward to roll up and when you don't need more them 50', you save the extra effort to unroll and reroll the cord. If you make your own cords realize there are various qualities of cord SJ or SJO and the fittings for the end will vary greatly in quality. If there is a Home Depot nearby they can get you set up with bulk cord. Rat...

 

[djradz]

Gary, based on 30 volts and 175 amps, my calculations show that to maintain 3% voltage, you can go a maximum length of 160 feet total circuit length if you use #10 copper or 100 feet total if you use #10 aluminum. Subtract the length of your existing feed (75 ft I think you said) from this to get the maximum length of your extension cord. Actually, you could probably go all the way to a 5% voltage drop if you really needed to get more length, but it sounds as if this won't be necessary.

 

[hazmat]

Gary,

Here's an online calculator StansElectric

You want to put in the max amps the welder draws at 240V, not the 175 amps at 30V that it welds at.

Here's a link to a table Power is everything Scroll down for the 120/240V table. NOTE MUST MULTIPLY BY 2 TO GET 240V VALUES.

Interesting to note, that when you jump up a size in wire, there is a significant difference in voltage drop or distance you can go for a given voltage drop.

Extension cords are used all the time for welders. We used to make them up at work using hubble fittings. 10/3 will get you pretty far at 240V / 30Amps.

 

[woodmills1]

I got some used street wire from a friend who runs a trailer park and hooked up one whopper of a 220 extension cord. not too flexible but don't have to worry about voltage drop. trouble was being aluminum conductor it was tricky to wedge them three wires into a 30 amp drier plug and receptacle.