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I'm building a light installation and would love to use a sleek fabric-wrapped cable. As I need at least 5 cables I thought of using an Ethernet-cable as they come in nice forms and shapes.

The problem is that I'm powering some 144LEDs (https://learn.adafruit.com/adafruit-dotstar-leds) which require 8A at 5V.

Based on this (https://networkengineering.stackexchange.com/questions/43734/what-is-the-voltage-used-in-ethernet-lines-utp-cables) I assume that it wouldn't be an issue. But as I don't want my project to become a fire hazard of some sort I want to make sure that "misusing" an Ethernet cable won't be an issue.

Any help would be appreciated.

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    \$\begingroup\$ Welcome! How far from the power source will you be? The main problem with high current, low voltage applications is power loss in the cable. \$\endgroup\$ – awjlogan Mar 17 at 14:17
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    \$\begingroup\$ Did you work out the voltage drop at 8 A on the length you are considering? You should be able to find an online calculator. Don't forget to include the return path. \$\endgroup\$ – Transistor Mar 17 at 14:17
  • \$\begingroup\$ Consider ambient temperature. If the connections are subject to 70°C, they could fail, possibly starting a fire. 5v*8A = 40W. You could use a higher voltage, say 24vDC boost converter. 40W = 24v*x --> x = 1.6A (plus losses) across the cable, then buck this down to 5v for the LEDs. \$\endgroup\$ – rdtsc Mar 17 at 14:57
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    \$\begingroup\$ Better to run 40V@1A through it. (24V@1.7A is a good compromise) \$\endgroup\$ – Brian Drummond Mar 17 at 15:02
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    \$\begingroup\$ You can't put 8A through ethernet cable. Supply 48v through the cable, and put a 5v output converter at the point of use. \$\endgroup\$ – Neil_UK Mar 17 at 17:14

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