Changing lights in alcove in, these lights are controlled by a pull switch. Disconnected one light, put loose wires in a connector block, tested continuity, it was ok, checked with power on had 240 volts. Removed the second light and checked as before (continuity) this time had a dc voltage reading, same with the other light. Switched off pull switch, again checked continuity with meter, it had switched back to ac, pull on switch and it goes back to dc. All I’ve done is disconnect the wires, any idea why it should do this. The house has recently had a new box fitted by an electrician so I can’t see a problem with polarity, having said that the lights where working ok before is disconnected them,could the pull switch for some reason just become faulty.

  • Could you clarify how exactly you were issuing your multimeter? There is no AC or DC when measuring continuity, and continuity is not measured in volts. – brhans Jan 10 at 14:26
  • Define how you determined it "switched" from AC to DC etc. – mike65535 Jan 10 at 14:59
  • Hi, thanks for replying to my question. I was using a digital multimeter, which is a Fluke T3w. With power off, I put my probes across live and neutral wire, (which where in a chocolate block) from the switch. The earth symbol together with the buzzer operated. On disconnecting the second light, and doing the same, I found that the dc light came on, checking the previous light again I found this the same, a dc reading. Nothing else done other than disconnect the lights and put the tails into chocolate blocks. I connected one of the lights, and turned on the power, reading of 230 dc ??? – Keith Rennie Jan 10 at 17:32
  • Hi, I have removed wall lights and fitted the loose tails into their respective junction boxes, ready to connect the new lights, on removing the first light, with the electrical box isolated, on testing across live and neutral I had an ac ground reading. But when I did the same on light no 2 I had a dc ground connection, nothing else has been done, could this indicate a faulty neutral cable running in the wall. All other lights are working correctly, just have problem since disconnecting wall lights. – Keith Rennie Jan 10 at 20:10

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