Hello -- Two questions about grounding a standard 4-foot fluorescent
fixture, fed from conduit. The fixture is grounded with a grounding
screw and pig tail connected to the circuit ground wire. I expect that
the conduit is supposed to be grounded via its physical connection to
the fixture. However the fixture is painted, and doesn't make a good
electrical connection with the conduit fittings. I can scrape a bit of
paint off around the knock-outs to improve the connection. Is that
what is usually done?
Also, I note that the fixture is actually composed of five separate
pieces of stamped sheet metal, which were painted prior to assembly.
They don't actually make good electrical connection with each other.
In particular, there's no continuity between the sheet with the
grounding screw and the panel with the knock-out where the conduit
connects. This seems really odd. If there isn't continuity between the
different sheets, I'm not sure how the grounding is supposed to work.
Connecting them electrically would probably mean completely
disassembling the unit and sanding or scraping off the paint where the
different parts connect. Do people actually do this?