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Doug Miller Doug Miller is offline
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Default wire size and amp rating

In article , Ned Simmons wrote:
On Wed, 29 Aug 2007 12:14:38 -0500, "Karl Townsend"
wrote:

I have an underground wire that I think is called #8-3 but I can't find any
numbers on it. The OD of the insulation is 0.238" on each of the three
wires. That in turn is in another insulated jacket for underground. Each
wire is a seven stranded unit, the O.D. of this is 0.145" and each wire
measures 0.048". What's the wire size here?


#8 sounds right.


8's not that big -- unless he's measuring the insulation, not the wire, in
which case he has a meaningless measurement.


More importantly, I need to know amp capacity. There's four of these #8?-3
wires in a conduit for four feet going from the main to underground.
(Multiconductor may reduce amp rating?)

I want to go 40 amp circuit breaker. Am I OK


Unless the insulation is something very unusual (rated less than 60
degrees C) it should be fine.


And that's why I told him he needs to find the markings on the cable.

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

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