240 volt lighting control

[Jeremiah1]

Can 240 volt single phase Metal Halide street lighting be reliably controlled using a sufficiently rated 120 volt photocell and just controlling one leg?

jeremiah1

 

[iwire]

It works fine but is an NEC violation. 410.54(B)

 

[Bob NH]

Can 240 volt single phase Metal Halide street lighting be reliably controlled using a sufficiently rated 120 volt photocell and just controlling one leg?

jeremiah1

If you open only the one leg, there will be 240 Volts across the 120 Volt photocell. Pfffft!

 

[iwire]

If you open only the one leg, there will be 240 Volts across the 120 Volt photocell. Pfffft!

Not normally.

Photo cell electronics are wired between Line and neutral, not line and load.

 

[yanici]

There are photo cells available that can operate from 120V to 277V(kind of like universal voltage). I know intermatic is one brand I've used. There may be others also. They make plug-in, button, and long neck styles. Just check the amp ratings.:wink:

 

[boater bill]

Use the photocell to operate a lighting contactor. Put the fixtures across the contactors and all of the loads and controls play together nice.