Auxiliary Contact Current

[Joeisi]

Hello,
I have a board that is being designed that I need to interface a 120V AC squirrel cage motor Auxillary Contact. In order to determine the type of relay I need, I need to know the maximum current one of these starters can draw through the button. I was wondering if anyone knew what the max current was so that I could plan accordingly.

 

[crutschow]

That would depend upon the specs of the starter. Don't you have that?

 

[BradtheRad]

The safest path is to reckon there could be several amps going through the relay.

Copied from:

https://en.wikipedia.org/wiki/AC_motor

"This is why a squirrel cage blower motor may cause household lights to dim upon starting, but does not dim the lights on startup when its fan belt (and therefore mechanical load) is removed. Furthermore, a stalled squirrel cage motor (overloaded or with a jammed shaft) will consume current limited only by circuit resistance as it attempts to start. Unless something else limits the current (or cuts it off completely) overheating and destruction of the winding insulation is the likely outcome."

 

[Joeisi]

I do not have the specs, as I am designing this board to be able to start lots of motor starters.

 

[crutschow]

Then I would suggest looking up the specs on several different motor starters and see what the coil current range is.