Lighting contactor question

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tom_jlr

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I have a 3 pole, mechanically held contactor, with a 120v control coil (Eaton #ECC04C1A3A) controlling 277v lighting circuits.

Can I use 3 single pole lighting switches to control the contactor? Do I need to use 3-way and 4-way switches? Can I use a realy or low voltage switches to control the contactor?
 

charlie b

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Are you saying that the contactor has a single phase 120 volt coil? And are you suggesting that the coil be turned on or off using a set of three single pole switches? If the answers are both yes, then this won't work. How can you wire more than one single pole switch in such a way that operating any one will turn on and off the lights, regardless of the positions of the other two? It cannot be done. If you use two switches, then they need to be 3-ways. If you use any more than two switches, then the remainder have to be 4-ways.

Welcome to the forum.
 

infinity

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Generally mechanically held contactors are switched by one SPDT switch, also called a 3-way switch. If you want to use more than one switch then you need to setup the system using only momentary contact switches. Otherwise the system will not work. With a relay accessory you can set them up to turn off and on with one single pole switch too.
 

dkidd

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All switches could be single pole double throw center off momentary. They could be wired in parallel.
 

infinity

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If you used an accessory relay (like ASCO #47) you could use any standard combination of 3 and 4-way switches to switch the control circuit on and off.
 

iwire

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Generally mechanically held contactors are switched by one SPDT switch, also called a 3-way switch. If you want to use more than one switch then you need to setup the system using only momentary contact switches. Otherwise the system will not work. With a relay accessory you can set them up to turn off and on with one single pole switch too.

Actually with a mechanically held contactor you can add as many momentary switches as you would like.

It is with electrically held contactors that switching gets trickier for multiple locations.
 

tom_jlr

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So, if I use single pole double throw center off momentary switches, I could use three or more of them with no issues, no extra wires?
 

infinity

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So, if I use single pole double throw center off momentary switches, I could use three or more of them with no issues, no extra wires?

No issue just wire them all in parallel. You could add a momentary time clock too with this setup just wire that in parallel too.
 

infinity

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Ahh when I read '3-way' I assumed you meant a standard 3-way set up when you were actually talking about SPDT momentary switches. :cool:

Actually I did mean a standard 3-way switch. If you're using one switch for on and off control a standard 3-way will work with a mechanically held contactor (at least the ASCO versions that we install).:grin:
 

iwire

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Actually I did mean a standard 3-way switch. If you're using one switch for on and off control a standard 3-way will work with a mechanically held contactor (at least the ASCO versions that we install).:grin:

It can work but it makes the purchase of a mechanically held all but worthless (IMO) and you would be stuck with no more than one switch location.
 

infinity

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It can work but it makes the purchase of a mechanically held all but worthless (IMO) and you would be stuck with no more than one switch location.

Worthless if multiple switching locations are needed. Pretty valuable if you need to turn on and off 12 circuits with one switch.
 

realolman

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the less expensive electrically held one would work just as well, but the momentary switches with the mechanical one allow multiple parallel switch locations
 

iwire

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Worthless if multiple switching locations are needed. Pretty valuable if you need to turn on and off 12 circuits with one switch.

I am not saying a contactor is a waste, just the added costs of mechanically held would be a waste. I would use an electrically held contactor for about 1/3 to 1/2 the cost of the mechanically held unit.

The last one I ordered was about 500 for electrically held and 900 for mechanically held.
 
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