welder question

[reggiejr]

Thanks for all the input so far everyone.
I have used quite a few welders over the years both mig and stick so i'm pretty confident with the welding aspect but i never really payed attention to the makes or the particulars of the welders I've used just settings ect.
They were not mine so i really haven't learned much about brands and different models comparing specs and such so all the specs look like Chinese to me.
I have tried one small flux core 120v miller years ago and i wasn't to impressed but i figured technology probably improved with those by now?
Everything else I've used has been 220v and that seemed to be the way to go but i cant spend big money on a top of the line model like we have at work i just want to dub around on my own stuff once in a while at home.
If i were to just go ahead and replace my line to the garage for a 220 welder what gauge wire would you guys recommend?
The line feeding the garage now is a 10-2 i'm not sure if that is adequate or not for a welder.
My generator would be easy for me to use because its right there were i would be welding and it would give me an excuse to run it once in awhile between outages.Thanks again for all the advise :thumbsup:

 

[cowski]

a 150 amp inverter welder will just about max your generator at full power.a welder any bigger would be a waste ,unless you plan on upgrading the gen or run a 220 wire.i still like my 140 everlast.it will run on 110 or 220 on a 5500 watt generator.if you get one plan on upgrading the welding Leeds.

 

[Groo]

the 211 only calls for 25 amps of power. Millermatic® 211 Auto-Set? with MVP? - MIG - Miller That generator should handle it fine.

If you want power in the garage, run a sub-panel. Doing that is on my to-do list. I had 120v power in the garage, but the chain-link fence pole snipped that wire, and I also want to weld out there, so I need both 240 and 120. Might as well just run the panel. I will want another sub panel in the shed I plan on using as a pottery studio too, so I plan on running from the house to the shed to the garage. As for what line; it depends on how much power and how far.

for 100 amp power, probably single or double aught for the hots with aluminum wire. Neutral and ground can probably be down-gauged a bit, especially with these types of loads were all the power save for the big stuff could be handled on 1 or 2 breakers.

 

[cowski]

sorry i should have said stick inverter welder.

 

[Texasmark]

On running your wire, one needs the distance and the anticipated load plus whether or not it is buried vs airborne. Then there is the insulation type. I have a book that gives the line sizes for a 2% voltage drop over a given distance.

On sizing the N and the safety ground, the N is there for unbalanced loads. A balanced load from a 220v service would be one where you either were running a 220v appliance or you had two equal wattage 110v loads connected to opposite sides of the feed and N. In this case they feed each other off the mains (two hot lines) and the N is really out of the picture.

However, if you have one with say a 220 watt 110v load hooked to one main and N and a 110 watt load hooked to the other main and N then the N would have to carry the extra amp that the 220watt load needs. The safety ground should never carry current unless you have a "hot chassis" in an all metal electric drill or something metallic that has a main accidentally connected to the case. Then it would have to be large enough to carry enough current to keep that hot chassis from developing enough voltage to shock you.

That's the way I remember it but it has been awhile.

HTH,
Mark

 

[Groo]

That is how I remember it too. If you are running a 20 amp load on one leg and a 5 amp load on the other, the Neutral will only have to carry 15 amps. Don't be surprised if they try to sell you 00/4 to run the sub-panel. as explained above, it is unnecessary. 00/2 -2/2 should be more than enough, but I'm not 100% sure what code is for this. If you have a choice between 120v and 240v in the future, pick the 240v tool and keep an eye on keeping things as balanced as possible are good practices in general and should keep the electrical bill down some. I'd probably run lighting on one leg and outlets on the other leg for 120v circuits in the garage and you should be more than fine. If my math is right, you should be able to safely run 3x20 amp 120v breakers per leg (6 total) and still be perfectly safe in a worst case scenario with a 2 gauge neutral. I believe ground is required to be a minimum of 6 gauge Cu, 2 gauge Al is the equivalent of 4ga CU, so that is more than enough for a ground. Honestly, I still haven't figured out why they need a separate ground and neutral wired to the sub panel, but its code. I am not sure if running your own ground spikes at the garage would make it so you don't have to run a ground from the main panel.

 

[Ken45101]

I am not sure if running your own ground spikes at the garage would make it so you don't have to run a ground from the main panel.

Code is very specific about adding ground rods. You may NOT substitute a ground rod for a 4th conductor in a situation like this. That could be dangerous.

As has been mentioned, the conductor size is important not only to handle the required current, but also to minimize voltage loss under load. A couple of years ago, we added a barn for the RV. Lowe's didn't have the wire I wanted so I ended up with 12-3 w/ ground. I cannot take my compressor out there to top off the tires, the starting current drops the voltage too low for the compressor to start even though it normally runs on a 15 amp circuit.

Ken

 

[Groo]

Code is very specific about adding ground rods. You may NOT substitute a ground rod for a 4th conductor in a situation like this. That could be dangerous.

As has been mentioned, the conductor size is important not only to handle the required current, but also to minimize voltage loss under load. A couple of years ago, we added a barn for the RV. Lowe's didn't have the wire I wanted so I ended up with 12-3 w/ ground. I cannot take my compressor out there to top off the tires, the starting current drops the voltage too low for the compressor to start even though it normally runs on a 15 amp circuit.

Ken

I had a feeling that the 4th wire would be required by code, but I still can't understand why. it seams to me that the one neutral/ground wire and ground spikes should be more than enough. I'd think being close to a true earth ground would be even safer than a just a 4th wire. I guess I've never really studied this type of thing in depth, so maybe I am missing something.

The underlined is why I suggested 00 for the hots instead of 0. I doubt there will ever be a 120v unbalanced current load of greater than 20 amps in this type of application, so its only the 240v stuff you'd need to worry about voltage drop with. really, even 2 gauge Al for the hots would probably be plenty for a small welder and a few lights for quit a long run.

I know what you are saying about needing heavier gauge to start a motor. When my garage electrical was working, it would run my compressor easily, but when I plugged it into another outlet on the, about 1/4 the distance from the breaker (or closer), but downstream of some crappy wiring, it took plenty of trips down to the breakers box before I actually got it to run.

 

[Ken45101]

I had a feeling that the 4th wire would be required by code, but I still can't understand why. it seams to me that the one neutral/ground wire and ground spikes should be more than enough.

I'm not an electrical expert. Maybe someone with better knowledge can give a better answer.

The neutral wire is to carry the return current for the 110 hot lines. The ground wire is to provide a chassis ground so that you don't get shocked if something shorts out inside the case. They have different purposes.

Prior to the 1960's or 70's, three wire was all that was used, neutral and ground was shared. Then they changed the code, I assume for good reason.

During very dry weather, the dirt can pull away from a ground rod. I don't think outbuildings are supposed to have separate ground rods but that's getting into an area where I am not knowledgeable.

Ken

 

[Texasmark]

I still haven't figured out why they need a separate ground and neutral wired to the sub panel, but its code.

The reason is just what we were talking about and Ken said. If the 220 feed is unbalanced the unbalance current flows through the N. This gives you a voltage drop on the N wire and could present a shock hazard, especially if the consumption is a long way from the power source whereas the run would be long, wire resistance significant (considering), and hence enough voltage developed to present a shock hazard to ground (earth ground or to something connected to it). So they add a wire that normally carries no current and hence provides the panel ground reference at point of use.

Mark