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A bit of an oddball question. We bought, through a US distributor, a ceiling light fixture that was made in Europe (Netherlands). It is a metal fixture, connected to the ceiling via a metal chain, which connects to mounting bracket which has a grounding wire attached to it at the bracket only. The lamp wire is 2 wires, one with blue sheathing, one with brown sheathing. The bulbs are E14 which I connected with an e14 to 12 reducer. I checked on EU standards and blue wires are neutral, brown is for line. When I wired it, it did not work but it was not hung at the time (I was testing it). It was sitting on cardboard box that was on the floor. A non-contact tester lit up when near the fixture (all over it) when the switch was on. I immediately disconnected it (after turning off the breaker). This is a well made fixture from a reputable company, wires appear intact, no obvious reason to think there is some kind of a short. It did not trip the breaker when hooked up.

My questions are 1) Using a multimeter, how could I test the fixture if re-wired to ensure that it is not actually live (maybe the non-contact tester is measuring a floating ground?)?

2) Is it possible that a fixture will not work without being connected to the "ground?" I have had that happen with a step down transformer which would not work until the ground wire was hooked up. No idea how or why that was that way (if someone knows please let me know).

Thank you very much for your help.

Lastly, I am contacting the seller to find out if this is approved for sale in the US. The company website does list the US as an area of distribution. I think they also make some of the fixtures for a large US light seller so I'm pretty sure it's ok. Thank you again.

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  • I doubt a fixture with European wire color codes and E14 lamp bases would be approved for installation in the US.
    – DoxyLover
    Apr 26, 2017 at 7:57
  • You almost certainly don't need to connect ground for the fixture to work, but your description makes me suspect that you have a broken/floating neutral leading up to the fixture. Did you have an existing fixture there and is there any chance that it was 'bootlegging' its neutral from the ground wire?
    – brhans
    Apr 26, 2017 at 13:15
  • The house is very old, There are 3 wires at the fixture, 2 which are spliced (neutral), 1 which is the line from the switch. The old fixture was from the 1940s and likely original to when they had added electric (house is from the 20s). No problem with the neutral before with the old fixture for what it's worth.
    – Elmo
    Apr 26, 2017 at 13:44
  • @DoxyLover Trade treaties with some other countries oblige us to honor their certifications if reasonably equivalent to our own, so a TUV should carry weight here. Apr 26, 2017 at 19:19
  • Are you sure your power source is good? If yours had hot neutral reverse, that would cause this also. Apr 26, 2017 at 19:20

3 Answers 3

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So I've got it working, I'll post a few things in case it's helpful for someone else in the future.

  1. Using a multi-meter I tested continuity throughout the fixture on both sides of the circuit (both little round circles at the base of the bulb sockets), and everything was intact - so no shorts.
  2. My non-contact tester is a capacitive coupling tester which will detect electrostatic fields in the absence of flowing current. The entire fixture tested "hot" because there was line power going into it but no path outwards (see 3). It was not an energized fixture however as the line power was contained within the intact wiring
  3. Not all reducers are created equal (or fit in that particular light). The e14-12 reducer that I was using was not getting good contact with the base of the socket. I took the fixture to a local lamp store where we test fitted 3 different reducers until we found one that worked. At least one bulb needed to be connected to complete the circuit. Since none of the reducers was contacting the socket sufficiently to work there was no circuit made - leading to #2 above.
  4. From my reading and discussion with the lamp store people: European fixtures are powered at 220-240V, at that voltage less current is needed to power a bulb which is why they are able to use smaller gauge wiring. In the US, at lower voltage more current is needed to power a given wattage bulb. Wire resistance is pretty much fixed so a higher current over a fixed resistance generates more heat, I believe the equation is power is proportional to IxIxR. In my application this is ok as I am using LEDs at a much lower wattage, I am also not using 240V bulbs which would demand a much higher current flow to work (if they even could). Hopefully I summarized this correctly (and am not wrong).
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To verify the wiring is correct use your ohm meter function on your meter and verify the neutral is connected to the outside shell of the socket. also verify brown is going to the center contact of the socket. The ground is not required for the lamp to function but would be a good idea to be connected at the top mount if available with a metal fixture. The problem may be in the adapter so make sure to test the fixture without the adapter if the first test shows an open (especially on the center of the socket). Some bulbs and adapters do not screw in far enough to make contact with some fixtures I have seen this on a few occasions. To know if it is legal in the U.S. we would need to know the certification stamp(s).

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  • I will re-confirm that the wiring is correctly identified. How do I test the light fixture itself to make sure it's not electrified? I assume "positive" test lead goes to the fixture but what am I "comparing" it to with the negative?
    – Elmo
    Apr 26, 2017 at 17:41
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No. No device needs a ground wire to function.*

The whole point of a ground is that it's not a conductor in NEC meaning, i.e. does not carry working currents under normal use.

If a device needs a wire to function, that wire is a working conductor and can't be a ground. If that wire is coded/colored as a ground, this is called "bootlegging", someone is misusing ground as a working conductor. I'm looking at you, all you smart switches which claim not to need neutral and still work with LEDs, and mysteriously will not work if ground is not hooked up, gee...

The only exception I can think is a test instrument (e.g. 3-light tester). Or I suppose a machine might have a protective circuit that tests for the presence of ground before allowing start-up, but I have never heard of such a machine.


* except for certain smart switches made to operate on switch loops; they need neutral and bootleg it off ground, and UL permitted this because the amount of current is very tiny. Those smart switches require ground. It is not normal for devices to require ground for functional reasons, only safety reasons.

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