I am getting an old Lincoln 225 stick welder given to me. You know the type,
I think about ever farmer has had one or still does. It says that it pulls
up to 50 amps on max. , I will be setting it up about 25 ft. from the
electrical box. What size electrical wire would you run to the electrical
10 gauge is the smallest you can consider. At full power with 10 gauge wire
you would lose about 6 volts, dropping your 240 volts down to 234, probably
ok. With 8 gauge wire the voltage drop would only be 3.8 volts. Since you
probably rarely will run the welder flat out, 10 gauge is probably ok. This
is assuming copper wire.
For wire buried in the house walls, #8 is the very minimum with #6
preferred (watch your codes carefully!). If you are talking about an
extension cord, you can go one size smaller than the NEC would allow
since it is in the open air and stays cooler.
I use a 25' #10 extension cord on my 225 amp welder, works fine. But I
rarely run it over 135 amps ouput.
#6 is probably the best size and may be required for a 50A breaker although
there may be allowances for using a 50A breaker with #8 since a welder is an
intermittent load. You would have to check your codes to see if this is
allowed in your area and you may have to connect the welder is such a manner
that it is the only load possible.
Personally I would go with #8 and a 40A breaker unless you think you are
going to run it flat out. I have a 225A Miller that I run on the end of
about 75' of #8 but granted, I am usually under 160A. I did run a rod with
it cranked up to 225 without any problem. I have never tripped the breaker
even with the rod stuck down an glowing (about 130A setting). If #8 is OK
for you, it is cheaper than #6 and much easier to work with due to its