ECN Forum Forums General Topics of the Trade General Discussion Area hooking up a miller welder??

sorry i probably didnt explain it clearly. but if you click on the image again it gives two choices on hooking up the welder.
-60a time delay fuses with 8awg conductor
or
-80a breaker with 8awg conductor

i couldnt find a 80a breaker so i want to use the 60a time-delay fuses. my question was, from the sub-panel to the 60a time-delay disconnect, can i use 8awg with a 40a breaker to feed the 60a time-delay disconnect??

thanks for your guys advice....

Kojunho, you are reading the chart incorrectly

The table you posted shows subnote (1) for circuit breakers
"Consult factory for circuit breaker applications"

Subnote (2) for Time delay Fuses recommends 60Amp fuses.

Subnote (3), which is the one that you keep referring to, is not for circuit breakers, it's for Normal Operating (non delay) Fuses, and is where you are getting your 80 Amp figure from.

Simply put, a welder with a 54 amp load will not work reliably, when turned up, on a 40 Amp breaker. A 60 Amp time delay fuse will not serve any purpose whatsoever when fed with a 40 Amp breaker.

You should call Miller, see what they recommend for a circuit breaker size, and then follow their instructions.
The same goes for the conductor sizing.

Just a little anecdotal experience. I have a 230a "buzz box" that said it should be on a 48a breaker (unobtanium). Since I didn't have any easy way to put in another circuit when I bought it about 37 years ago I just put a dryer plug on it and plugged it into the 30a circuit my dryer was on. It has never blown a fuse or tripped a breaker and I still run it on 30a circuits.
I may have never used it on the highest setting with the biggest rod it will handle, using it at the maximum duty cycle but I doubt anyone else does either.