DC Cable Size question

Discussion in 'General Electronics Discussion' started by Quintrex4, Oct 24, 2014.

1. Quintrex4

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Oct 17, 2014
Last edited: Oct 24, 2014
2. hevans1944Hop - AC8NS

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Jun 21, 2012
It depends on how much resistance 22.9 m of cable has. What the heck is "bi-metal" speaker wire? Copper-clad aluminum perhaps? I would use 18 AWG copper zip cord.

3. (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

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Jan 21, 2010
OK, first thing, is it 14 strands per conductor, or 7 per conductor?

Let's assume it's 7. So the cross-section is 7 * 0.16 = 1.1mm^2 so the effective diameter is about 1.2mm

The resistance of this is probably something like 0.017 ohms per metre. The total length is about 46m, so the resistance is around 0.78 ohms.

At 0.16A, the voltage drop will be 0.13V. That's probably not significant.

4. (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

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Good point. I assumed copper.

5. Quintrex4

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Oct 17, 2014
Great! Running off limited information from the suppliers site. 0.13V drop is insignificant for what I need it for.

6. (*steve*)¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥdModerator

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That assumes it's copper. For aluminium, the resistance is just under double copper's.

The voltage drop will probably still be under 1/4 of a volt.