To connect a welder about 15 feet from breaker box. The welder says
primary amps 40. A wire chart on a website shows #6 as 37.5 amps.
Will #6 be close enough or should I use #4? I know the welder will
not be drawing full amperage most of the time, only on spikes.

Thanks

Be advised, the welder will NEVER pull what it says it will. They are
highly overrated. Besides a #8 would be fine for 40A. 10ga on a 30a
breaker will work fine.

Steve Barker


wrote in message
...
To connect a welder about 15 feet from breaker box. The welder says
primary amps 40. A wire chart on a website shows #6 as 37.5 amps.
Will #6 be close enough or should I use #4? I know the welder will
not be drawing full amperage most of the time, only on spikes.

Thanks

If the welder actually draws 40 amps, #6 copper would be fine



wrote in message
...
To connect a welder about 15 feet from breaker box. The welder says
primary amps 40. A wire chart on a website shows #6 as 37.5 amps.
Will #6 be close enough or should I use #4? I know the welder will
not be drawing full amperage most of the time, only on spikes.

Thanks

wrote in message
...
To connect a welder about 15 feet from breaker box. The welder says
primary amps 40. A wire chart on a website shows #6 as 37.5 amps.
Will #6 be close enough or should I use #4? I know the welder will
not be drawing full amperage most of the time, only on spikes.

Thanks

Consider what would happen if you put in too small wire. You get to do it
again, and pay more.

Do it once. Do it right.

What if you decide to get a little bit bigger welder? Or if you like
welding, and use it enough to really heat up the wiring?

Copper is expensive now, but nowhere near the cost of doing it twice.

Steve

In article , wrote:
To connect a welder about 15 feet from breaker box. The welder says
primary amps 40. A wire chart on a website shows #6 as 37.5 amps.

Wow, I wonder where they came up with that. The National Electrical Code shows
#6 copper at 55 amps.

Will #6 be close enough or should I use #4?

Neither -- #8 copper is quite sufficient for 40 amps. If you're using
aluminum, then you need #6. But in no case do you need #4 for a load of only
40 amps.


--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

On Sun, 17 Dec 2006 01:17:49 GMT, (Doug Miller)
wrote:

In article , wrote:
To connect a welder about 15 feet from breaker box. The welder says
primary amps 40. A wire chart on a website shows #6 as 37.5 amps.

Wow, I wonder where they came up with that. The National Electrical Code shows
#6 copper at 55 amps.


Here's the site: I thought it shoul be higher than that....
http://www.interfacebus.com/Copper_Wire_AWG_SIze.html
It seems to me like the old cable type service entrances for 60A
service were #6-3 plus ground (wrapped around the bundle).


Will #6 be close enough or should I use #4?

Neither -- #8 copper is quite sufficient for 40 amps. If you're using
aluminum, then you need #6. But in no case do you need #4 for a load of only
40 amps.

Thanks

wrote in message
...
On Sun, 17 Dec 2006 01:17:49 GMT, (Doug Miller)
wrote:

Here's the site: I thought it shoul be higher than that....
http://www.interfacebus.com/Copper_Wire_AWG_SIze.html
It seems to me like the old cable type service entrances for 60A
service were #6-3 plus ground (wrapped around the bundle).
I'm no electrician so I'm not sure what they're giving the specs for but
just think of it this way. According to that table, 14 ga is only rated to
5.87A. We all have a lot of problems if that's the case given the number
of 15A circuits we have in our houses! I'd look for another chart or
better yet, get into an NEC manual. If memory serves, 8 ga THHN/THHW or NM
should work fine for 40A.
Cheers.
cc

In article , wrote:
On Sun, 17 Dec 2006 01:17:49 GMT, (Doug Miller)
wrote:

In article ,
wrote:
To connect a welder about 15 feet from breaker box. The welder says
primary amps 40. A wire chart on a website shows #6 as 37.5 amps.

Wow, I wonder where they came up with that. The National Electrical Code shows
#6 copper at 55 amps.

Here's the site: I thought it shoul be higher than that....
http://www.interfacebus.com/Copper_Wire_AWG_SIze.html

Below the table, it does say "The National Electrical Code [NEC] requires
their own cable sizing for premises wiring. Refer to the NEC rules to
determine building wiring, as this page relates to electronic equipment
wiring."

This is then followed by a sample list of wire guages and supposedly
NEC-permissible ampacities, which I will *not* reproduce here because it's
wrong.

It seems to me like the old cable type service entrances for 60A
service were #6-3 plus ground (wrapped around the bundle).

Sounds about right.


Will #6 be close enough or should I use #4?

Neither -- #8 copper is quite sufficient for 40 amps. If you're using
aluminum, then you need #6. But in no case do you need #4 for a load of only
40 amps.

Thanks

Good luck, and stay safe.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

On Sun, 17 Dec 2006 13:41:16 GMT, (Doug Miller)
wrote:

In article , wrote:
On Sun, 17 Dec 2006 01:17:49 GMT, (Doug Miller)
wrote:

In article ,
wrote:
To connect a welder about 15 feet from breaker box. The welder says
primary amps 40. A wire chart on a website shows #6 as 37.5 amps.

Wow, I wonder where they came up with that. The National Electrical Code shows
#6 copper at 55 amps.

Here's the site: I thought it shoul be higher than that....
http://www.interfacebus.com/Copper_Wire_AWG_SIze.html

Below the table, it does say "The National Electrical Code [NEC] requires
their own cable sizing for premises wiring. Refer to the NEC rules to
determine building wiring, as this page relates to electronic equipment
wiring."

This is then followed by a sample list of wire guages and supposedly
NEC-permissible ampacities, which I will *not* reproduce here because it's
wrong.


I looked at that chart again, and it really is screwy. I was too
quick to find a chart and did not spend much time reading all of it.
So much for that POS chart.....

Thanks