CAT5 for PSU

I have to run +/- 24v, +/-15v and +12v from a central PSU to a number of boxes. All draw audio box type current. Is there any reason I shouldn't use CAT5 cable? It sure is cheap. I thought I'd use the sheilded stranded type and run 0v separate from shield.

I think there is a better wire to use for that application, but if that's what you have lying around, I would probably do it.

I'm willing to buy better wire but I'd like to know what's wrong with the CAT5. It seems like it can handle the power.

What is "audio box type current"? How long are the cable runs? The insulation on Cat 5 was never meant to isolate large amounts of current and the long runs could heat up slightly if it were any significant amount. Expect voltage droop on long runs of small gauge cable under load conditions too.

Then again it could be such low current you'd never notice.

Audio box type current is about 500mA per channel. So 1000mA over a bipolar supply line would be about right. The runs would be 15-20ft.

The CAT5 cable I see is 22-24ga and rated for 300v. This seems like similar specs to the control cable that is usually used for this. The pairs are twisted. Does this affect performance?

CAT5 is really like antenna cable. It is designed for connecting low current RF signals between boxes over long (up to 330 feet) runs. For over 500 mA DC, I personally would not go less than 18 GA. Stranded of course. Like Svart sed, you have to consider the resistance of the wire, and solid wire is not good for power interconnects. It is found almost exclusively behind walls and tacked down-electrical, alarm, data, telco, control, doorbell, etc. Stranded is flexible and gives more conductor surface area for HF noise conducting on the chassis/ common wire/s.

Can you do it? Sure! Someone ran ribbon cable under the carpet around his studio to feed cue mixers, like it was multipair, unbalanced I think, and it works. I could never sell that to a client, same as a CAT5 power cable.

Mike

[quote author="sodderboy"]I personally would not go less than 18 GA. [/quote]

Thanks. I guess that's the answer I'm looking for. It's time to open the Belden Catalog.