DC current through a stainless steel/copper wire
DC current through a stainless steel/copper wire
(OP)
I'm looking at suspending some low volatage (<30V) lighting with a 7x7 304 stainless steel aircraft cable. I also want to run 30V DC through the cable to power the light. So the suspension cable is also supplying the power. I will be running 4 separate cables (only 2 will be used to supply power). The closest cables will be about 2 feet apart. To keep the conductivity high I want to replace the stainless steel 1x7 core of the cable with a 1x7 copper strand. This will be used indoors in office buildings, grocery stores and the like. Will there be any corrosion issues with the copper or stainless steel wires?





RE: DC current through a stainless steel/copper wire
Mike Halloran
Pembroke Pines, FL, USA
RE: DC current through a stainless steel/copper wire
RE: DC current through a stainless steel/copper wire
RE: DC current through a stainless steel/copper wire
Technically it may be feasible, but, I don't see much chance of getting it approved without spending a ton of money.
"An 'expert' is someone who has made every possible mistake in a very narrow field of study." -- Edward Teller
RE: DC current through a stainless steel/copper wire
rysep; Why can't you find something off-the-shelf?
Keith Cress
kcress - http://www.flaminsystems.com
RE: DC current through a stainless steel/copper wire
If it is sold as a system and has an approved LV power supply, then it might be acceptable. But I'm not aware of anyone doing it with steel conductors. But I could be wrong.
It happens a lot
"An 'expert' is someone who has made every possible mistake in a very narrow field of study." -- Edward Teller
RE: DC current through a stainless steel/copper wire
RE: DC current through a stainless steel/copper wire
I have also seen similar lighting to this but it usually is something that spans from one wall to another. The lights that attach to the cable are very light weight. We are suspending much heavier lights from the ceiling and need a cable that is stronger than a tin or zinc plated copper cable. So the load is really taken by the staninless wires while the current is going through the copper wires.
My main concern is corrosion because we are running DC through copper wire in contact with stainless steel wires.
RE: DC current through a stainless steel/copper wire
It compises a loosely twisted pair of stranded insulated wire. Four of the strands were steel, three tinned copper (or the other way round).
What I remember most is field splicing the stuff; the only approved splice is a square knot. The steel makes it pretty difficult to tie a knot in the wire; it's very stiff.
[ I got to splice it because I had borrowed a spool that was alleged to be a continuous unbroken mile. It wasn't; it had been cut in several places, and the ends knotted together, not with square knot splices, just unstripped knots, so I couldn't get a signal through it until I unrolled all of it and put it back together. )
Mike Halloran
Pembroke Pines, FL, USA
RE: DC current through a stainless steel/copper wire
Mike Halloran
Pembroke Pines, FL, USA
RE: DC current through a stainless steel/copper wire
Keith Cress
kcress - http://www.flaminsystems.com
RE: DC current through a stainless steel/copper wire
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RE: DC current through a stainless steel/copper wire
RE: DC current through a stainless steel/copper wire
The Signal Corps wire was not stainless. I've seen it rust in "legacy" installations.
It's also pure misery to unwrap a half mile of it off a tank sprocket.
old field guy
RE: DC current through a stainless steel/copper wire
Keith Cress
kcress - http://www.flaminsystems.com