how to 3-way 208v highbay Lts

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can this be done witout a contactor. I will have 2 - 2pole breakers feeding them and seems like I would have to have 2 relay coils doing it that way.
 
When I wire high-bays (or low-bays, for that matter), unless it's just a very few of them, I always do the switching with contactors. Keeps the voltage drop low, and lets you use little, low-current conductors to the switches. They just switch the coil(s) of the contactor(s).

If you choose this method, do a favor for the next guy. Install your contactors in a "normal" place, where they might be found without a treasure map, Green Lantern secret decoder ring, and 4 phone calls to the Psychic Hotline. Label some of your wiring at the contactor, so the next guy knows what conductors go to what switches.
 
transman2 said:
can this be done witout a contactor. I will have 2 - 2pole breakers feeding them and seems like I would have to have 2 relay coils doing it that way.
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Can it be done?


Sure.

Will it be NEC compliant?

No.
 
transman2 said:
can this be done witout a contactor. I will have 2 - 2pole breakers feeding them and seems like I would have to have 2 relay coils doing it that way.
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Just get a 4 pole contactor -- one coil
 
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transman2 said:
Does this mean I will have to have 2 contacors
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Not unless you like it that way. Lighting contactors are available up to 12 pole normally, and you can get general purpose contactors in 4-pole quite easily. Be advised that a control system is not required to break every hot wire, if you choose to go that route. You can break one hot of each circuit, and use a 2pole contactor.
 
mdshunk said:
You can break one hot of each circuit, and use a 2pole contactor.
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Marc he can not do that for the same reason he can not do that with the three ways.

410.54(B) prevents it.
 
iwire said:
Marc he can not do that for the same reason he can not do that with the three ways.

410.54(B) prevents it.
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Thanks, Bob, for that quick correction. I've never done it that way, but it seems that 410.54(B) is specific to HID fixtures. Any other type of 2-pole load, and it would be okay. I guess this is a safety issue, related to maintenance and repair.
 
Marc I would not do it that way either....but on the other hand we often used SP Thermostats with 208 / 240 baseboard heat.

Kind of a personal double standard.:roll: :-?
 
iwire said:
Marc I would not do it that way either....but on the other hand we often used SP Thermostats with 208 / 240 baseboard heat.

Kind of a personal double standard.:roll: :-?
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I guess. I use DP stats on baseboard heat, because I've never seen a SP stat with a marked "off" position. Lacking that marking, you need a disco within sight of the heater.
 
mdshunk said:
I guess. I use DP stats on baseboard heat, because I've never seen a SP stat with a marked "off" position. Lacking that marking, you need a disco within sight of the heater.
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What section requires a disconnecting means within sight of a baseboard heater?
 
iwire said:
How about 419.(B)(1)? [sic]
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424.19(B)(1)

Sure, but the AHJ's down my way consider that a breaker "capable of being locked in the open position" must have the lockout adaptor installed on the breaker. Line voltage double-pole stats are nearly 5 bucks a piece cheaper at the supply house anyhow, so that's an easy decision to make.

I'm not that passionate about the matter either route a guy goes, truthfully.
 
What I suspect Marc is that when I was doing this the AHJs where not pushing LOTO as hard as they do now.

If I was doing condos now I might find I have to change my old ways.
 
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