Do you install a 2 pole switching device on 208V or 240V lighting?

[tortuga]

Poll for the lighting folks here.
A common installation around here is to have a 2 pole timer open one leg of two 240V or 208V lighting circuits. Leaving one leg hot to the ballast.

Or a photocell that only opens one leg of the circuit (typical twist lock street light or pole parking lot light)

In the case with the MH lights they are cord and plug connected to a receptacle that is timed, however only one leg of the receptacle is switched.
Another job I am thinking of is a big box store with a GE lighting control panel using a 1 pole latching relay that fits in a 1/2" K/O on some 208V Line to line lighting circuits.

I am looking at three code sections:
210.10 (2005 and 2008 NEC) however the supply branch circuit does not have a grounded conductor and the switching device is not the disconnecting means.
410.93 (2008 NEC) (410.48 2005 NEC) however the timers are switching a 240v receptacle that a ballast cord and plug connects to, then the ballast connects to the mongul base lamp holder that is not of the switched type. (and there still is no neutral ).
410.140(B) (2008 NEC) 410.54(B) (2005 NEC) Might apply to the cord and plug connected ballast.
Note; I am not talking about the disconnecting means.
Thanks in advance.

 

[hurk27]

most newer fluorescents now have those moldex plugs on them, and most of the HID lighting I do inside is twist-loc, but I have always used a 2-pole switch just because there are to many who would expect the power to be removed if the switch is off.

so are you the one on the bicycle with the white dog in front of you?

I zoomed in on you cords you posted as location and all thats there is a restaurant called Charlie's or The Wandering Goat Coffee Co.:grin:

 

[dicklaxt]

Does 210.4.B apply???

dick

 

[don_resqcapt19]

Take a look at 410.54(B) in the 2005 or 410.104(B) in the 2008. Most fixtures operating at that voltage will be of the electric discharge type.

 

[tortuga]

so are you the one on the bicycle with the white dog in front of you?

I zoomed in on you cords you posted as location and all thats there is a restaurant called Charlie's or The Wandering Goat Coffee Co.:grin:

The Wandering Goat is my favorite coffee shop.

Does 210.4.B apply???

The circuit I am thinking of is just a 240V or 208V line to line, with no neutral Going from a 2 pole breaker to a single pole relay or single pole timer to a receptacle. Feeding these cord and plug connected HID lights.

You have a regular 2 pole 20A breaker as your disconnecting means and a you might have a cord and plug disconnect at the light.
Does the controller have to disconnect both ungrounded conductors?
like one of these single pole latching relays:

 

[don_resqcapt19]

...
Does the controller have to disconnect both ungrounded conductors?
...

The section I cited says it has to.

2005 NEC 410.54(B) Switching Where supplied by the ungrounded conductors of a circuit, the switching device of auxiliary equipment shall simultaneously disconnect all conductors.

Note that this section speciffically applies to the switching of the circuit and not to the disconnection of the circuit.

 

[tortuga]

Agreed 410.140(B) (2008 NEC) 410.54(B) (2005 NEC) looks that way.
It also looks like it is not a code violation to install the 240V receptacles on a timer or control with one leg switched just once they plug the lights in it is.
It is common in other appliances like a 240V heater, oven element to have one leg switched by a control so I never really thought of it in terms of the HID lighting.

 

[dbuckley]

This is another one of those situations where although code allows just single pole switching, deep in your heart, you know that a double pole switch is what should be fitted, so that when its off it's off, not just half off with a shock potential for the unwary.

 

[don_resqcapt19]

This is another one of those situations where although code allows just single pole switching, deep in your heart, you know that a double pole switch is what should be fitted, so that when its off it's off, not just half off with a shock potential for the unwary.

This is one of the cases where the code does not permit single pole switching.

 

[tortuga]

This is one of the cases where the code does not permit single pole switching.

I think he was referring to my comment about the receptacles and the electric heaters.

I guess the only reason for this is protecting an unqualified person from opening the lens and contacting the exposed live metal screw shell. Interesting.
I was just looking at the OSHA website trying to see what they require for lamp replacement. It looks like 1910.333(a)(1) Note 1 mentions "removal of illumination for an area." as a reason for working on live parts or not having the circuit locked off and tagged.
So if OSHA allows lamps to be replaced by a QP on an energized circuit then the lamps can be replaced wile the circuit is actually fired up OR if they don't allow it (not enough of a reason or whatever) then it has to locked and tagged off at the disconnect, and there is a disconnecting means within sight of the ballast or lamp holder. Thus the only logic of 410.140(B) (2008 NEC) 410.54(B) (2005 NEC) is there is no way to polarize the mongul base and make the button the always "hot", so we have to assume the metal screw shell is an exposed live part? Where as live elements in a single pole switched heater are inside the case unless you remove the grill. But wait that sounds like the lens.