High amperage single phase plugs 60 amp.

[Portable Welder]

I just bought a new 350 P Aluminum welder, All of the plugs in the shop are 50 amp single phase plugs except for my tig welder that has a big Russel Stoll plug that weighs 20 lbs and is rated for 60 amp 3 phase.

So my question is: If its rated 60 amps 3 phase that means each prong is rated to carry 20 amps each, however I'm only using 2 prongs because I only have single phase so each prong is now carrying 30 amps at maximum capacity.

So that has me thinking that the 50 amp single phase plugs are actually rated higher than the 60 amp 3 phase plug I'm using on the tig welder.

However, if you look at 20 lb Russel stoll aluminum housing plug you would think differently.

So I'm in a situation where I need a 60 amp single phase plug for the new welder, because I use the welder in different areas of the shop I would rather not have it directly wired into a disconnect.

[raferguson]

The plugs are rated based on 100% duty cycle, but welders have much lower duty cycle, especially when the power is turned up all the way. I would just use whatever 50 amp single phase plug you are already using.

Richard

I just bought a new 350 P Aluminum welder, All of the plugs in the shop are 50 amp single phase plugs except for my tig welder that has a big Russel Stoll plug that weighs 20 lbs and is rated for 60 amp 3 phase.

So my question is: If its rated 60 amps 3 phase that means each prong is rated to carry 20 amps each, however I'm only using 2 prongs because I only have single phase so each prong is now carrying 30 amps at maximum capacity.

So that has me thinking that the 50 amp single phase plugs are actually rated higher than the 60 amp 3 phase plug I'm using on the tig welder.

However, if you look at 20 lb Russel stoll aluminum housing plug you would think differently.

So I'm in a situation where I need a 60 amp single phase plug for the new welder, because I use the welder in different areas of the shop I would rather not have it directly wired into a disconnect.

[shovelon]

The plugs are rated based on 100% duty cycle, but welders have much lower duty cycle, especially when the power is turned up all the way. I would just use whatever 50 amp single phase plug you are already using.

Richard

Ditto. I run mine off a 50 amp plug without issue.

[Portable Welder]

Thanks for your input but I would really like to find the proper plug to run it at max out put if needed.

[USMCPOP]

I would think the 60A Russelstoll plug is 60 A per phase.

[Aeronca41]

Right on

I would think the 60A Russelstoll plug is 60 A per phase.

USMCPOP is correct. NEMA ratings for connectors are per phase. Your plug is good for 60 amps per pin.

[mbramble]

"....So my question is: If its rated 60 amps 3 phase that means each prong is rated to carry 20 amps each, however I'm only using 2 prongs because I only have single phase so each prong is now carrying 30 amps at maximum capacity....."

Not sure what the question is here but each prong of that 3 phase 60A plug is rated at 60A. A device requiring 60A is not expecting 20A on each of the 3 phases but 60A on each phase. And when using single phase, it needs 60A on each of the 2 hot logs - not 30A on each.

[WillieB]

When we supply a three phase receptacle we divide load between three supply conductors. A 60 amp single phase circuit at 240 volts can supply 14400 watts of power. A three phase circuit uses three windings, but only one more lead. At the same voltage, and amperage the increased power delivered is by a factor of the square root of three or 1.73. 1.73x14400=24912 watts. Ben Franklyn considered electricity to be a fluid. If it were a fluid three pipes would flow 50% more than two. Fluid need not return to the point of origin.

Oh, a three phase receptacle/plug will work fine on single phase. It will, however present a hazard should someone plug a real three phase load into it.

[H80N]

6-50

Good.. Bad or Indiferent... the Nema 6-50 is pretty much the De-Facto standard plug for single phase 240 welders..
there have been several threads on this subject ...
have seen everything from Sync 250 to MM350P...Dyn350... Powermax 1000 etc etc .... in many shops wired with 6-50.. having run for many years with no problems....

There seems to be plenty of capacity built into that 6-50 design...
rather than the plug being a limiting factor... I believe the rating is keyed to the capacity of the wiring and breaker intended to be supplying it... and if used as intended... you can believe that a receptacle using a 6-50 is wired for at least 50 amps..
And yes.. this usage probably defeats the rating system...

Oh dear.. here comes a ...Sh.t...Storm...

[Sberry]

The 50A plug will work fine for that machine.

[Portable Welder]

Okay then, My 50 amp plug single phase plug that I use on my miller matic 252, MM200 etc. The 50 amp plug is 50 amps per hot leg.

[Portable Welder]

okay then looks like I need to buy another Russel stohl plug and run it off that if I want to meet code.

[Broccoli1]

okay then looks like I need to buy another Russel stohl plug and run it off that if I want to meet code.

You can use the Multiplier to find out if the 6-50 connector will work within code

Applies to conductors and connectors.

http://ecmweb.com/qampa/code-qa-45

[Portable Welder]

Thanks for everyone's input.

[WillieB]

okay then looks like I need to buy another Russel stohl plug and run it off that if I want to meet code.

A three phase receptacle, supplied with single phase power does not comply with code.

Single phase 60 or 70 amp combos aren't cheap!