Help getting welder wired in!

[Rara Avis]

As a licensed master electrician, been a journeyman since 1970, I can tell you, IF the folks who write the National Electrical Code, even has the slightest thought Article 630 which covers Electric Welders was not correct or safe it would be changed. For a Arc welder (hobby) with 20% duty cycle at the highest setting, take the nameplate rating X .45 that is what the wire is sized on. For welders: Fuse or C/B shall not be rated at over 200% of the conductor ampere rating. (This does not factor in voltage drop for long runs of wire.)

Local codes may vary. Welding outlets are for welders and should be marked so, not for plugging your toaster into...

I thought welders were plugged into the Dryer outlet...

 

[GaryBDavis]

Make sure EVERY ground wire is attached to any metal box it is spliced in or passes through.

I'm going with a single 10AWG ground conductor in the main 2" EMT run and splicing in the appropriate size ground wire to feed each drop. From what you are saying, I need to bond the ground wire to the metal junction boxes where I drop down. Is this the only place I need to do this or do I have to bond the ground wires in the outlet boxes also? It seems most outlets are "self grounding".

BTW, thanks for everyone's help.

 

[Inspector507]

I'm going with a single 10AWG ground conductor in the main 2" EMT run and splicing in the appropriate size ground wire to feed each drop. From what you are saying, I need to bond the ground wire to the metal junction boxes where I drop down. Is this the only place I need to do this or do I have to bond the ground wires in the outlet boxes also? It seems most outlets are "self grounding".

BTW, thanks for everyone's help.

Yes attach the ground wires to the outlet boxes. A "self grounding" outlet is usually used with a grounded box and THEN the outlet is grounded as soon as you attach it to the box.
A true "self grounding" outlet is not something you'd usually find in a box store.

 

[gemini5362]

Yes attach the ground wires to the outlet boxes. A "self grounding" outlet is usually used with a grounded box and THEN the outlet is grounded as soon as you attach it to the box.
A true "self grounding" outlet is not something you'd usually find in a box store.

Would a self grounding outlet be one where the green screw for the ground is connected to one of the tabs where you screw the outlet into the box ?

 

[Inspector507]

Would a self grounding outlet be one where the green screw for the ground is connected to one of the tabs where you screw the outlet into the box ?

No. The "self grounding" type have a retaining device on one end of the yoke to make contact between the screw, the yoke and the box. See this picture from the Leviton website.

 

[BobRip]

As a licensed master electrician, been a journeyman since 1970, I can tell you, IF the folks who write the National Electrical Code, even has the slightest thought Article 630 which covers Electric Welders was not correct or safe it would be changed. ..

I expect you are correct, but the history of the code shows that things which were OK years back are not allowed today (Ex. Carrying current on the dryer ground, ungrounded outlets, one ground rod, 60 amp panels in house, no GFI, etc.) I suspect that it took multiple incidentes to get the changes approved.

I believe if you are wiring a welding shop then Article 630 is OK. If you are wiring your garage with many different possible loads it may not be the best way to go.