pulling wire thru steel conduit

Is it possible/code to pull three #10 and three #8 wires thru a 3/4" steel conduit?
Thanks, Matt
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It's probably not physically possible and definitely a code violation. You also have to consider that when you pull multiple conductors through a conduit, you must derate the capacity of the conductors as well

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snipped-for-privacy@hotmail.com wrote:

If you have no turns, you could probably get 6 #10 through, but I don't think it'll do you much good.
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snipped-for-privacy@hotmail.com wrote:

Looks good to me.
40% fill for 3/4" pipe is 0.2100 sq in.
3 #10 THHN = 0.0552 sq in.
3 #8 THHN = 0.1119 sq in.
Throw in a bare #10 equip ground = 0.008 sq in. (250-95 table)
TOTAL = 0.1751 sq in. (less than allowable fill)
-------------- Apply the de-rating factor from Note 8:
#10 THHN 40 Amp X 80% = 32 Amps, so 30 Amp protection is suitable.
#8 THHN 55 Amp X 80% = 44 Amps, so 40 Amp protection is suitable.
Jim
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Speedy Jim wrote:

Electrically looks OK, but how's he going to get all that around the bends?
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He can use a wire pulling lubricant like Ideal Yellow77. http://www.idealindustries.com/IDEAL-EZ/prodcat.nsf/Tables/Yellow+77+Plus?OpenDocument

suitable.
suitable.
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snipped-for-privacy@hotmail.com ( snipped-for-privacy@hotmail.com) said...

It depends on what the insulation is! It is the cross sectional area that matters, as you are not supposed to exceed 40% of the conduit's area.
If all these wires have T90 Nylon insulation, then their cross section area is only 31.8% of the conduit's. If they are TW75, then they are 39.6%, so they would also fit. If they are RWU75 EP, then they are 63.8% of the conduit's fill.
I have a "conduit calculator" available for free at http://daxack.ca that comes with cross-section data for a number of different types of wire.
--
Calvin Henry-Cotnam
"Never ascribe to malice what can equally be explained by incompetence."
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Calvin Henry-Cotnam wrote:

Good link. Thanks!
R
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