[AT] Wire size for welder?? Help welder people!

[Francis Robinson]

At 12/8/04 2:44:00 PM, you wrote:
>John,
>
>Don't overlook the fact that breakers are to protect the wiring, not the device.  If you're running from a 50 
amp breaker, you need #6 wire.  The more correct way to look at that is that you size the breaker according to 
the wire you run.  A 50 amp breake
>r will not protect #10 wires.  They will overheat and become a potential fire hazard before the breaker trips 
unless the cause is a sudden short.
>    If the welder requires a 50 amp breaker for operation you need wiring heavy enough to sustain a near 
capacity current draw for an indefinite time period.
>
>Bigdog



	Hi Bigdog:

	That is an "extremely" good and important point... An awful lot of guys never grasp that consideration. 
The "bigger is better" thing kicks in and they want to hook small loads to these huge breakers so that one will 
never trip. Back when I was selling appliances I would go into a home and find every fuse in their fuse box was 
a 30 amp slow blow. Some of these folks had little more than a TV and a few lights and were in old houses 
that were wired extremely light. In most of those cases 15 amp fuses would have been more than adequate 
and much safer. My rule is to fuse any circut as lightly as I possibly can without blowing fuses (or tripping 
breakers). Fusing too heavy for the wire is like setting the pop-off valve on a steam boiler at a higher pressure 
than the pressure capacity of the boiler.



"farmer"


Francis Robinson
Central Indiana USA
robinson at svs.net