Syncrowave 250 wiring check/questions

[landon303]

Hey guys, newbie here.

Have done some searching/asked a friend so I'm not at a COMPLETE loss. Anyway:

My current set up is a 200A input breaker into my panel. From that, there's 8 spots for breakers, all of which are full. In particular, I'm running my MIG on a 50A breaker, runs ~15' to a "dryer style" 3 prong plug, via #10 wire. I'd now like to add in the Syncrowave 250. My plan is to:

Pull the 50A breaker, replace w/ 100A. Change #10 wire to #6. (NEC question: Can I run it in the existing 3/4" metal conduit? Or is it time to bump that up in size?). This run will go to a sub panel, which contains the 50A breaker I replaced, and a lead back out to my outlet to run the MIG. I will NEVER be using BOTH welders at the SAME time. I will then be wiring in my syncro 250 at the sub panel. That's where my question comes in: can I wire it in here as a plug, so that I can move the unit around? Or is hardwiring the only "good" choice? Maybe a 6/3 extension cord hard wired in is what I'm after? I'd like to be able to roll it out into the carport area, about 25' away, (welder is on a cart, too) and tackle some on-vehicle welding if needed.

Anyway, if someone could eye-over my intended setup and tell me "good to go" or "do this instead" that would be awesome!! Planning to tackle this tomorrow AM.

Thank you all!!

[wb4rt]

Hi, Landon.

I'm not an electrician, but since no one else has answered, I'll add what I can. I have a Sync 250, running it plugged into a 50 amp circuit with 6 gauge wire. I'm just a hobbiest, but haven't popped the breaker in 2 years of running it that way. I would just put a plug on it, and swap with the MIG and see how it works for you. Then you can add another 50 amp plug later, to eliminate plugging and un-plugging.

[USMCPOP]

100 Amps to a sub-panel using #6? No way. Get some advice from a professional sparky. My sub-panel with a 100A breaker uses 2/0 aluminum.

[Aeronca41]

USMCPOP is right on. The absolute minimum alum wire for a 100 A brkr with a 60 degree C temp rating is 1/0, and the 2/0 is great if you will have any sustained loads in your shop along with your welder. DO NOT put a 100 A breaker on #6 wire unless you live next door to a paid fire dept who will be there in seconds when the fire starts! See Natl Electrical Code Table 310.15.B(16) in current (2014) version or 310.16 in 2008 version. Not sure about the ones in between without looking them up out in the shop. Separate columns for copper and alum.

[Aeronca41]

USMCPOP is right on. The absolute minimum alum wire for a 100 A brkr with a 60 degree C temp rating is 1/0, and the 2/0 is great if you will have any sustained loads in your shop along with your welder. DO NOT put a 100 A breaker on #6 wire unless you live next door to a paid fire dept who will be there in seconds when the fire starts! See Natl Electrical Code Table 310.15.B(16) in current (2014) version or 310.16 in 2008 version. Not sure about the ones in between without looking them up out in the shop. Separate columns for copper and alum.

Checked the 2011 code. The Allowable Ampacity table applicable to this situation is 310.15.B(16), same as the 2014 book. The content in all 3 years is obviously the same, only the table number in the code is changed. Please be safe!

[DATEC]

Check the other thread about wiring that was discussed just the other day. In there you will find links we had provided to that person that will point you in the correct direction. But as always please call your locals to make sure that it is correct for your needs, I will not tell you how to short cut electric EVER! Like taking one lag from a 220 outlet to make a 110 outlet, oops! That is one example of what you could do for a short cut but I will never recommend. So I say if your willing now to make it work then do it right. I don't want to come off harsh but the other guy was thick headed, willing to change if needed and when told to make the corrections decided on bare minimum,not good enough in my book. Read the post and you will have your answer. Let us know what you deside but be safe.