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I am using a 6 core shielded cable. In this 3 wires are used for a sensor and 3+1(shield) is used for a analog camera. All the cores take DC supply.

Sensor(3 wires)

  1. (+)24 volt supply,
  2. (-)minus,
  3. output (24 volt digital and PNP output)

Output switching Frequency : 800 Hz

Response time : 600 microsecond

Note: No load supply current <10 mA & switching current is max 50mA, resistence load.

Camera 3 wires and 1 shield,

  1. (+)5volt supply
  2. (-)minus
  3. Video signal

and the Shield is grounded

The issue is, there is lot of noise in the video that I see in the screen. I could make out that the noise is because of the power supply and signal from sensor. Because when ever I switch off the sensor, the noise disappears. Ideally I should have a separate cable for video signal and sensor, but because of space constrain (overall dia< 8mm) in my application, I cannot do it. Can electrical experts advice me on removing the noise from the cable ? Note: Current carried by the cable is in the order of milliAmp. Thank you all in advance.

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  • \$\begingroup\$ This is not really answerable without specifics on the sensor's current draw with respect to time, and output signal. Often some filtering (LC circuit at lower frequencies, ferrite beads at higher) would be a solution, but selecting that requires detailed information on the sensor both to pass the required current and to make sure that the sensor's output can be passed back. \$\endgroup\$ – Chris Stratton Jun 22 at 15:47
  • \$\begingroup\$ What is the nature of the signal from the sensor? How fast does it vary? Is it analog or digital? Please edit your question. \$\endgroup\$ – TimWescott Jun 22 at 17:07
  • \$\begingroup\$ Use additional capacitance, on BOTH power rails, at their loads. And perhaps ferrite beads. This reduces the rate-of-change-of-current, and reduces the magnetic coupling voltage. \$\endgroup\$ – analogsystemsrf Jun 22 at 17:29
  • \$\begingroup\$ @TimWescott: Thank you. Edited the question. Kindly check if all the necessary information is added. \$\endgroup\$ – Soma Sundaram Jun 23 at 4:59
  • \$\begingroup\$ Hi everyone, Will it help if I use twisted pair cables instead of straight or parallel cables that I am using now ? \$\endgroup\$ – Soma Sundaram Jun 23 at 5:20

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