Contactor coil

[dvcraven0522]

Simple question - I am controlling a 3-phase load 50amp 208V with a 3-pole contactor. Is the coil voltage need to be of the same rating. In other words is the coil rated for 3 phase or 208V single phase. Seems like a stupid question.....but I only need to pull in the contacts correct?

What would the coil burden be rated?

I am confused on what to specify.

Thanks

 

[LarryFine]

Coil voltage has nothing to do with load voltage. Coil voltage should be whatever the control voltage is.

Typically, it's either 120v from a transformer, or it can be the L-N or L-L voltage if there is no transformer.

Do you know the voltage that supplies the control circuit, or whether or not there is a control transformer?

 

[dvcraven0522]

Coil voltage has nothing to do with load voltage. Coil voltage should be whatever the control voltage is.

Typically, it's either 120v from a transformer, or it can be the L-N or L-L voltage if there is no transformer.

Do you know the voltage that supplies the control circuit, or whether or not there is a control transformer?

120volts

 

[LarryFine]

120volts

Then, that should be your coil voltage.

 

[synchro]

Simple question - I am controlling a 3-phase load 50amp 208V with a 3-pole contactor. Is the coil voltage need to be of the same rating. In other words is the coil rated for 3 phase or 208V single phase. Seems like a stupid question.....but I only need to pull in the contacts correct?

What would the coil burden be rated?

The contactor coil is a load that draws current, as opposed to a current transformer coil that supplies a current to a burden resistance.
Typically a contactor coil will specify an inrush in volt-amps or current draw, and a "sealed" or "holding' VA or current that is drawn after the contactor operation is completed.

 

[GeorgeB]

What would the coil burden be rated?

I am confused on what to specify.

You have some great answers; do you want the cheapest thing available, or ??? What does your customer or manager want used?

As an ESTIMATE, I looked online for cheap; about 120VA inrush, about 15 VA holding.