Switches don't behave any differently, but it's reasonable to assure that an ordinary person -- without any knowledge of electricity or LOTO procedures -- can replace a burned-out lightbulb without risking life & limb. Mandatory, I would suggest.
You turn off switches to replace lamps?
rnatalie says: "Here, hold my beer..."
Yes, especially if I know or suspect that it's connected to two hot legs.
In a workplace with strict LOTO policies that probably is happening, typically larger places of employment have higher chance of this being the way it works. Homeowners, smaller businesses - many don't even know what LOTO is.
That makes sense, the NEC should require that. Thats a mini SDS
I don't see the point of grounding anything - especially if the ballast is located in the luminaire. This is listing issue and shouldn't be code issue anyway.
Lowest voltage no, but if a conductor to the lampholder is also a grounded conductor then that is the one that is supposed to be connected to the shell - 410.50.
Fault to what? Isolated secondary would have no reference to anything, fault either conductor to the grounded luminaire housing then that conductor becomes grounded, though I guess if you ground faulted the conductor connected to the center pin then you would have whatever operating voltage to ground is from the shell to "ground". Outside of that there is only potential between the shell and center pin. On autotransformer type the shell is supposed to be the "common" and also connect to grounded circuit conductor when one is used. If no grounded conductor then there is voltage to ground on the shell, if grounded conductor is used, there is at least any voltage drop of the circuit present between shell and ground though is probably not much voltage most the time.
My grandma had a floor-standing lamp that had a mogul-based center socket and three Edison-based sockets.
Ever had an HID lamp break off while removing it?
