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I have just been given an old and slightly damaged CCTV camera (a skip find) and am trying to figure out the correct wiring before applying 12V power to it.

The wires are coloured and labeled as such:

  • ACP - White
  • ACP - Black
  • 12V - Red
  • GND - Cable shielding
  • VBS - Yellow

The unit is marked as being able to run off DC12V or AC24V.

I am taking a guess that the two ACP wires are for the AC power source, and the Red wire and cable shield are for the DC. Does that mean the shield and yellow VBS are my video signal and ground?

There are no connectors as the cable is damaged.

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Although your guess about the wiring seems sensible, I would approach it this way:

  • Using any make/model numbers on the camera, search online for any technical information on that (or similar) models, which might apply.

    Manufacturers often keep similar connections between models of devices, so a technical manual for model "X" may be helpful with model "Y" from the same manufacturer.

  • Open the camera and look on the internal PCB for components (and PCB markings) close to each of those external connections.

    For example, if the two "ACP" connections go to a bridge rectifier and then a 7812 regulator, and the output of that regulator is also the place where the 12V wire connects, then you can confirm that you have identified the AC and 12V power connections.

  • In this context, "VBS" usually means a composite video signal (VBS = "Video Baseband Signal" or "Video, Blanking & Syncs"). A single yellow wire for the video output (using the camera's 0V rail for the video signal connector shield) is common, so again, your guess makes sense for this.

  • Since this camera was a "skip find" which may not work, then it's difficult for you to tell the difference between:

    (a) Correct wiring, but faulty camera; or
    (b) Incorrect wiring.

    Therefore even if you use the correct wiring, it may not work, of course.

Good luck!

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  • \$\begingroup\$ Thanks for your response. I've hooked up a DC12V supply to the GND and red wired. It seems to be working partially - the current draw is around 150mA, rising to about 450mA when the IR LEDs are on. Across the GND and yellow cable I get a 15.176KHz signal, but this gives a black screen on the TV that I've haphazardly wired it up to (via component in). Perhaps I should open a new question with this information? \$\endgroup\$ – Alex Holsgrove Nov 25 '17 at 13:06
  • \$\begingroup\$ @Alex - Thanks. Based on those results, the wiring seems correct. Unfortunately you might have scenario "a" that I mentioned - not unexpected in a "skip find". A question about repairing the camera would need to meet the criteria on this site for such questions - see: "Is asking on how to fix a faulty circuit on topic?". As it's a piece of consumer electronics, you would need to provide the camera's circuit diagram, provide relevant oscilloscope traces, show troubleshooting skills to narrow down the question - and it might still get closed. \$\endgroup\$ – SamGibson Nov 25 '17 at 14:48
  • \$\begingroup\$ Thanks Sam. The unit had some menu buttons soldered to one of the PCBs. Pressing these gave me a settings menu on the television which was great progress. Still no video. Unfortunately, after cleaning the lens module, something must have finally given up as I get no output whatsoever. Back to this skip with this! Thank you again for your help. \$\endgroup\$ – Alex Holsgrove Nov 25 '17 at 21:50

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