New parking lot LED mogul base screw in lamp for 1000watt 240 volt lamp

[Matt Mckenzie]

New LED mogul base lamps say rated for 120 volt through 277 volt. That means direct wire 240 volt and were good, but I thought code says that a screw shell of a lamp holder must always be grounded......?

 

[GoldDigger]

New LED mogul base lamps say rated for 120 volt through 277 volt. That means direct wire 240 volt and were good, but I thought code says that a screw shell of a lamp holder must always be grounded......?

It does, so that makes the usual sources of 208 and 240 rather problematic. But 277 should be OK from 480Y/277.

 

[JFletcher]

New LED mogul base lamps say rated for 120 volt through 277 volt. That means direct wire 240 volt and were good, but I thought code says that a screw shell of a lamp holder must always be grounded......?

410.50 says that when "the grounded conductor, where connected to a screw shell lamp holder...". 2 ungrounded conductors can be hooked up either way. 208V, 240V and 480V lighting are perfectly legal. Corner grounded deltas would have to have C (grounded) phase to the shell and polarity would matter if using AC or BC legs.

Iow, if you're using a grounded conductor, it has to go to the shell but there is nothing saying you have to use a grounded conductor - 2 hots is fine.