DC contactor aux outputs

[dave2brecht]

Can someone explain to me the function of the 2 aux. wires on a DC contactor? I'm using a Kilovac EV200 and am not sure what function these two white aux. wires provide or how to hook them up. Thanks.

 

[ScottyUK]

The two white wires are an auxiliary contact which is mechanically linked to, and electrically isolated from, the main contact. The auxiliary contact thus provides an indication of the position of the main contact for use in, for example, a control system. Without the auxiliary contact the best you could do would be to energise the coil and hope for the best. In some situations that would not be acceptable. The auxiliary contact and wiring is mentioned in the datasheet:

http://relays.tycoelectronics.com/datasheets/ev200.pdf

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Sometimes I only open my mouth to swap feet...

 

[dave2brecht]

I see. So the auxillary contact mimics the postion of the main contact.

I could wire one aux wire to a digital output and then read the other aux wire with a digital input to monitor the contactor status?

 

[jraef]

I don't see the need to connect to the output, just connect it to the source for your digital inputs.

JRaef.com
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[dave2brecht]

Oh, my source is 400V DC so I'll need to run a separate low voltage signal through the aux contact to read with a uC.

 

[jraef]

Correct, but that does not need to come from a digital output, it just needs to be the same source as for all of your digital inputs.

JRaef.com
"Engineers like to solve problems. If there are no problems handily available, they will create their own problems." Scott Adams
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[itsmoked]

It could also be a source of noise spikes into your sensing circuitry so you may want some optical isolation in between the two. You might actually need some sort of "other supply" if you do that.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com