Currently installing a replacement power supply for my old 24V LED Strip lights in the kitchen. Almost got it fully connected, but on the DC end I hit a snag:

I made a small error in my wiring reference, the picture of the cables running from the PSU to the LEDs is from an angle that does not tell me which of the white cables is the V+, and which is the V-. I only noticed this after I disconnected the old PSU from the connectors. The new PSU is NOT the unknown, it has clear labels.

So in short: What polarity does White cable with a Black Stripe running along its side usually indicate?

I referred to What do solid/striped lines on a wire indicate? but this in-question had black wire with white stripes.

I have a suspicion that it is Positive, due to white cable with yellow or red stripe being the positive, but I am unsure because its black stripe.

EDIT: Adding to the issue:

A potential Answer would always be use a "multimeter": However how do you use a multimeter to distinguish is for an input cable? A multimeter doesn't really output power to power the strip.

Second problem is that the wires in the PCB do not seem to be the wires I am getting on the other side. So would the best course of action be disassemble half the kitchen to rewire everything?

  • \$\begingroup\$ I suppose you should be able to find out with a multimeter? \$\endgroup\$
    – jcaron
    Jan 2, 2019 at 12:45
  • \$\begingroup\$ Or upload a picture that shows how the traces and other components on the PCB are placed (assuming it's mounted on a PCB). There's no fail-safe way to determine the polarity just by looking at the color of the wires. \$\endgroup\$
    – MartinF
    Jan 2, 2019 at 12:47
  • \$\begingroup\$ Your question really is a duplicate of the question you linked. If you read carefully you will see this, and the best answer is the same as that suggested by @jcaron \$\endgroup\$ Jan 2, 2019 at 12:49
  • \$\begingroup\$ @ElliotAlderson how exactly would one go about using a multimeter to test something that does not output power and only receives power? The second problem is everything else is obfuscated, since the wireing is done by the previous owner of the apartment. This includes: the wires in the LED are not the same wire as the wire that is near the PSU, meaning somewhere along the line there is a crimp. \$\endgroup\$
    – MAL
    Jan 2, 2019 at 12:49
  • 1
    \$\begingroup\$ If you've lost track of which connections on the LED strip are which, you'll have to reverse-engineer it in order to figure it out. \$\endgroup\$
    – Dave Tweed
    Jan 2, 2019 at 14:26


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