Welder / Wiring for Small Garage

[aircommuter]

For small wire sizes it is easy to remember if you just add 10 amps starting with #12 being 20. Then #10 is 30 amps , #8 is 40 amps and #6 is 50 amps. Wire length and temperature rating will change the amperage. Just a rule of thumb for the lower temperature. A larger welder could be used on the 30 amp circuit but it would limit how high of setting you could use and the duty cycle.

 

[WranglerX]

JUst use receptacle that matched power cord on welder, don't cut off plug of welder cord and graft on something different, this is no brainer because receptacles is not a problem.... And the NEMA 6-50 plug/receptacle combination has become industry standard (in most cases) .... Now all you have to do is determine wire size and breaker amperage.....

As a side note if you are using a 120/240 volt machine manufacture's recommend not cutting off plug on welder cord and grafting on something different....Will probably also void warranty...

 

[MAX-24-Dean]

pulled a page from the owners manual 24 amps on 240 volt so that is 80% of a 30amp circuit breaker so you will need a 30 amp CB and #10 wire unless it is a really long run.

Copied and pasted this note from your attachment.

4-4. Unit Specifications For 230 VAC
Do not use information in unit specifications table to determine electrical service requirements. See Sections 5-8 and 5-12 for information on con-
necting input power.

 

[aircommuter]

JUst use receptacle that matched power cord on welder, don't cut off plug of welder cord and graft on something different, this is no brainer because receptacles is not a problem.... And the NEMA 6-50 plug/receptacle combination has become industry standard (in most cases) .... Now all you have to do is determine wire size and breaker amperage.....

As a side note if you are using a 120/240 volt machine manufacture's recommend not cutting off plug on welder cord and grafting on something different....Will probably also void warranty...

Most 120/240 machines include an adapter. Some machines cone with a 4 wire plug and I have one that is 3 phase also.

 

[DaBear3428]

Copied and pasted this note from the your attachment.

4-4. Unit Specifications For 230 VAC
Do not use information in unit specifications table to determine electrical service requirements. See Sections 5-8 and 5-12 for information on con-
necting input power.

that is interesting, did not read that but then again we are not sizing a service we are sizing a feeder and the specified current draw is exactly what is used for that calculation.

 

[KennyG]

You shouldn't use 8/3 for a 30 amp breaker, the coded size for 30 amp is # 10 wire, any size larger than that with a 30 amp breaker could cause a problem. It would take longer for a breaker to trip

Huh??? You can use any larger size wire, it's just a waste of money. If you are depending on losses in the wiring to trip the breaker, you have some serious problems.

 

[KennyG]

#12 is 20 amp rated not 30.

I'm guessing that a #12 extension cable would be OK to use on a 30 amp welder because of the duty cycle. I think it would be frowned on for the building wiring because of the potential of hooking up a constant 30 amp load.

 

[aircommuter]

Huh??? You can use any larger size wire, it's just a waste of money. If you are depending on losses in the wiring to trip the breaker, you have some serious problems.

The only limitation on larger size wire is getting it to fit into the breaker or receptacle. Nothing to do with load.

 

[jimux]

All, question on wiring and breaker for my personal use small garage.

I have a 50 amp circuit from my house to the garage on 6/3 wire (black, red, white and ground).

I planned to wire a 30 amp circuit for welding with 8/3 wire, but is that enough for say a Hobart Handler 210MVP or a Mult-Handler 200 Multiprocess? I wouldn’t ever need to weld anything thicker than 3/8”.


Handler® 210 MVP™ MIG Welder | HobartWelders

Multi-Handler 200 Multiprocess Welder | HobartWelders

Will a 30 amp circuit with 8/3 work?

Electric works on demand .. so 6/3 run into a small panel and a 50 amp welder fed from that should be plenty for one person using one piece of equipment at a time. If you have a/c or compressor etc, switch them off if welding a long spell.

 

[DaBear3428]

I'm guessing that a #12 extension cable would be OK to use on a 30 amp welder because of the duty cycle. I think it would be frowned on for the building wiring because of the potential of hooking up a constant 30 amp load.

cords are considered manufactures wiring and falls under different jurisdiction, usually UL.