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#9445 - 04/30/02 07:31 AM wire size
butch Offline
Junior Member
Registered: 04/29/02
Posts: 1
Loc: helendale ca usa
I need to settle this debate once and for all. I have friends who say that a "thicker size braided wire" will carry more volts. The others say the same size "solid wire" will carry more voltage but harder to manage. I believe that the "solid wire" (same size) will carry more because there is less resistance than a stranded wire because electrons travel the path of least resistance. Can some one tell us who is right and why?

Many thanks
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#9446 - 04/30/02 07:46 AM Re: wire size
sparky66wv Offline
Member
Registered: 11/17/00
Posts: 2232
Loc: West Virginia
The ability to handle voltage is dependant upon the dielectric strength of the insulation, or the distance from other conductors and grounded objects (like overhead high voltage lines which are only insulated by the air).

Stranded and Solid wire, as far as I know will both carry the same current assuming they are the same size in circular mils, and made of the same material. Once again, the makeup of the insulation also comes into play here, the ampacity tables in the NEC point to this.

Clear as mud?
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#9447 - 04/30/02 07:54 AM Re: wire size
George Corron Offline
Member
Registered: 05/16/01
Posts: 717
Loc: Lorton, Va USA
OK, I'll ring in on this one.

The amount of voltage a conductor will carry is a function of its insulation, not cma.
Braided, and stranded conductors are used for 2 reasons in AC.

1. Ever try to pull anything larger than #8 in solid wire? Let's just say it don't corner too good....no "Wider is Better" here
Linemen use solid wire all the time in larger sizes, if you can form it outside the conduit, no problem, just a little more difficult to work with.

2. Never forget that AC has a property that is completely different from DC. Skin effect. Which means that current tends to travel on the outside of conductors and ignores the inside (on 400 hz, I've installed tubing cause the inside ain't being used anyway), so it is more efficient to 'break up' that pattern by using many strands and allowing it to 'skin' in multiple layers. The higher the current, the more efficient to use stranded or braided conductor.

That do it?
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#9448 - 04/30/02 10:20 AM Re: wire size
dana1028 Offline
Member
Registered: 01/09/02
Posts: 163
Loc: San Carlos, CA
Take a look at Table 8 - Conductor Properties - they list resistance on solid & stranded conductors.....every one listed shows lower resistance on solid conductors. (comparison is only avail for wire sizes 8 - 18).
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#9449 - 04/30/02 07:34 PM Re: wire size
sparky66wv Offline
Member
Registered: 11/17/00
Posts: 2232
Loc: West Virginia
I stand corrected (as usual...).

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Residential/Commercial Inspector
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