Davisonp
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- Reaction score
- 92
I had an odd one today.
I was investigating a problem with a light that was not working. As it turns out, it was multiple loose connections causing the problem.
The circuit is wired in old unearthed two core cables making the contact voltage tester a waste of time.
At the light fitting there is a single two core black and red cable appearing and connecting into the ceiling rose, however, a non contact voltage detector indicates that there is constant voltage on the black cable regardless of the switch position. This black cable is connected to the pendent neutral.
The light switch is a double switch and both switches have a two core cable to each switch. The non contact voltage detector does not detect any voltage at the switch unless the light controlled by that switch is turned on and working.
I was surprised that the non contact voltage detector only detects voltage at the switches when the light controlled by that switch is illuminated. The switch controlling a compact florescent lamp does not surprise me too much, but the second switch controls halogen bulbs, so I would expect there to be voltage potential at the light switch even if the switch is in the neutral cable and the switch has the lights off.
I am pretty sure both lights have the switch in the neutral. Can anyone confirm my theory, and why there appears to be no voltage at the switch when the halogen lights are turned off.
I was investigating a problem with a light that was not working. As it turns out, it was multiple loose connections causing the problem.
The circuit is wired in old unearthed two core cables making the contact voltage tester a waste of time.
At the light fitting there is a single two core black and red cable appearing and connecting into the ceiling rose, however, a non contact voltage detector indicates that there is constant voltage on the black cable regardless of the switch position. This black cable is connected to the pendent neutral.
The light switch is a double switch and both switches have a two core cable to each switch. The non contact voltage detector does not detect any voltage at the switch unless the light controlled by that switch is turned on and working.
I was surprised that the non contact voltage detector only detects voltage at the switches when the light controlled by that switch is illuminated. The switch controlling a compact florescent lamp does not surprise me too much, but the second switch controls halogen bulbs, so I would expect there to be voltage potential at the light switch even if the switch is in the neutral cable and the switch has the lights off.
I am pretty sure both lights have the switch in the neutral. Can anyone confirm my theory, and why there appears to be no voltage at the switch when the halogen lights are turned off.