On Sun, 09 Jan 2005 19:35:14 GMT, Bert wrote:
Bruce L. Bergman wrote:
You can use that 3-wire circuit, since there is no neutral load
(120V devices) in any welders I've seen. The neutral wire is bonded
to ground at the main panel, so for all practical purposes they're the
same thing - but they don't want you connecting any load returns (like
the dryer drum light or the oven light) to the safety ground.
That's what I thought; I just wanted to make sure I wasn't overlooking
some nuance of the neutral line concept that would end up wreaking
havoc on my welder (or me!).
If the main panel is convenient to the garage and has some capacity
left, you can add your own 50A welder receptacle - unless you have an
oddball main panel like a Zinsco or ITE Pushmatic, it can be done for
under $50 in parts. Just use a short piece of flex conduit and put a
surface mount plug below the panel - or if the panel is on the outside
of the garage wall, use a nipple out the back of the panel can, and
surface mount a 4S box right behind it in the garage.
Adding a welder receptacle in the garage is what I would like to do,
but I'm not sure that's an (economical) option. The main panel has
only one empty breaker slot, but I assume I would need two slots for a
new 240V circuit, correct? That means I would have to add another
panel (at a cost considerably higher than $50), right? Or are there
other options?
Tell us what brand panel you have, the model breakers it takes (or
can take) and what's in there now.
If you still have the label on the panel cover you're golden, it
will tell you whether you can use "duplex" breakers that fill one 1"
slot and give you two circuits, and which slots they will fit in.
Or the "quad" breakers that'll give you one 50A 2-pole for the
welder and two single 15A or 20A poles for the branch circuits you
unplugged to make room. (They also make 250-230 quads that will feed
the welder and dryer or water heater from the same 2" space - but
that's drawing too much power for the bus-bar stabs in most panels,
especially if it's an Aluminum buss panel.)
If the label is missing, does it have the stabs that have a "notch"
in the middle (Cutler Hammer/Challenger or Crouse Hinds/Murray/
Siemens) or the T fitting with the horizontal bar (GE)? That's what
you need to plug in thin breakers.
If it's a Zinsco, does it have "bumps" on the busbars to reject the
RC-38 double breakers? And on Federal Pacific, it needs to have the
right slots punched out on the busbars where the breaker plugs in.
Could I for instance connect both the welder outlet and
the range outlet to the same 50A breaker (and still meet code)?
Strict interpretation, no way. If an inspector sees it, he's not
going to pass it. You're not supposed to make splices inside the
panel for openers. And when you add the second branch breaker he'll
insist on a new load calculation, the numbers of which will probably
call for a service panel upgrade from 100A/125A to 200A, or 200A to
300A/400A"...
But as long as you don't try to cook and weld at the same time, and
you make a neat bolted connection in the panel, go for it. (And
remember that "we never had this conversation"...) ;-P
You'll need to splice the welder leads and the stove leads to a
short chunk of piece-out wire to go into the breaker (split-bolt
puttied and taped, or Polaris insulated splice), and then tuck
everything back in neatly so the cover goes back on.
-- Bruce --
--
Bruce L. Bergman, Woodland Hills (Los Angeles) CA - Desktop
Electrician for Westend Electric - CA726700
5737 Kanan Rd. #359, Agoura CA 91301 (818) 889-9545
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