Metal Halide - on 220V - any issues using 3 switches?

[bloomingtonmike]

So I want to hang my metal halide lights.
Planning 16 of them - 4 lights in 4 zones
I want to power them via 220V.

Any issues wiring each zone with two 3 way switches and a 4 way switch (3 entrances to shop)?

Each zone will be = One hot all the way through from CB to light
Other hot through the switches correctly for 3way/4way
Ground all the way through and to each switch and lights.

 

[nehog]

Do you worry about meeting code? Or the safety aspects?

 

[Charles (in GA)]

Attached, or detached building/shop/garage???? What wattage are the MH lights???? Are the fixtures multi-tap 120/240/277 or similar? or are they 240v only (single tap)???

I'm going to guess you are in the US? Bloomington, ILL?

I do not know for sure that the code requires both sides of the 240v to be interrupted by the switch, but its a safety issue to not do so.

Personally, I think you should pick the door most often to be the one you will first enter and last leave thru, and install double pole switches there. Forget the rest. Humans are creatures of habit and odds are, you won't be willy nilly coming and going randomly thru the three doors. Most likely you will almost always enter the building for the first time thru one door, flip on the lights, and then do your thing, eventually leaving thru the same door. MH lights need to be turned on and left on, given the start up time involved and the "wear and tear" they experience during each startup. Frequent startups shorten the bulb life dramatically.

Charles

 

[justsam]

Are you in the U.S.?
If so, I would not power them from 240V, and if I did ignore that than I would use a double pole switch.

 

[Charles (in GA)]

400w MH lights draw right at 480w, which is 4.0 amp on 120v. A 20 amp circuit is allowed to be loaded to 16 amps continously (lighting is a continuous load per the NEC) so 4 lights on a circuit is max but acceptable.

Being curious.... how high will the lights be mounted, and how big is the building???

Charles

 

[bloomingtonmike]

40x64x16 pole barn, 320watt low bay multi tap lights, IL.

I'll just wire contactors and do a switched 24v coil.

 

[wyliesdiesels]

Is this a residential garage? If so then lighting is not allowed by code to be 240v!

 

[Charles (in GA)]

Is this a residential garage? If so then lighting is not allowed by code to be 240v!

I think this is a detached structure as it is a pole structure.

210.6 Branch-Circuit Voltage Limitations. The nominal voltage of branch circuits shall not exceed the values permitted by 210.6(A) through (E).
(A) Occupancy Limitation. In dwelling units and guest rooms or guest suites of hotels, motels, and similar occupancies, the voltage shall not exceed 120 volts, nominal, between conductors that supply the terminals of the following:
(1) Luminaires
(2) Cord-and-plug-connected loads 1440 volt-amperes,
nominal, or less or less than 1⁄4 hp

It only applies to actual dwellings, not dwelling properties.

Charles