Is AC current on Cox Cable Coaxial cable (cable TV/Internet service) something I need to get fixed?.

Using a Fluke 322 clamp meter I measure 0.02 amperes AC reading on the COX coaxial cable, measured at the point where the cable exits the inner wall of my house. I get 0.00 - 0.01 amperes on the downstream side of the 3-way coaxial signal splitter (two TVs, and an Internet cable modem). The variance in measurements may be due to meter accuracy.

Using the clamp meter I measure 0.35 amperes AC on the Cox cable coaxial cable immediately upstream of the entrance box (outside the house). Additionally, the ground wire from the cable entrance box shows 0.28 - 0.31 amperes AC. This ground wire (solid copper AWG 10 or 12) connects to the household grounding electrode system which consists of three (3) properly sized grounding electrodes connected (bonded) together and spaced at 6 foot intervals. The ground wire run from the cable entrance to the ground rod connection is approximately 50 feet. The Cox cable in my neighborhood is underground. By the way, I ran the grounding wire from the coax outside entry point as the cable company had not grounded the cable at the house entrance.

It appears that most of the current from the Cox cable coaxial cable is bleeding off onto the ground wire.

This Issue is similar to the issue, subject: AC Voltage on Coaxial Cable (Cable TV) at: AC Voltage on Coaxial Cable (Cable TV)

  • 1
    Why did you decide to check it? What is the problem you are having that needs fixing? That's like less than 3 watts... I would guess that with an amp meter that reading might fall within the accuracy margin of error. Check the meter manual. – Jimmy Fix-it Sep 20 '20 at 1:18
  • Turn on a big load like a heater-fan, hair dryer, microwave etc. and check again. Did the number change significantly? – Harper - Reinstate Monica Sep 20 '20 at 2:42
  • Yes, turn on some big 120V loads and see if the number moves. Also, have you checked to make sure your coax grounding block is properly connected to the mains grounding system in your house? – ThreePhaseEel Sep 20 '20 at 3:18
  • that's 20 mA short circuit current ... how much current do you measure when you place your finger in the circuit? – jsotola Sep 20 '20 at 6:02
  • After you stick your finger in a socket as jsotola asks can you hold the clamp meter on your finger while standing on 1 foot under the power lines and provide us with that reading,,, not kidding try it or another body part and a .02 reading might be low,,, – Ed Beal Sep 20 '20 at 7:37

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