# How Does Line Frequency Affect Coils of a Contactor?

I am using a generator as my source voltage, which produces 240VAC @ 240Hz. I was planning to use the following contactor from TE: CONTACTOR 4PST 40A 240V

In the datasheet it says this contactor's coil's activating voltage needs to be 50/60Hz. Now what happens if I feed 240VAC @ 240Hz to the activating coil?

I have asked the same question from DigiKey and TE support people, and they just said it won't work; but they did not explain WHY it won't work. So, I was hoping if someone could explain it to me why it won't work.

Thanks

• -- Clarification : What generator are you using that is 240 VAC @ 240 Hz? Normal generator output frequencies are 50/60/400 Hz. – R Drast Nov 15 '18 at 14:45

An AC coil presents a specific impedance at a specific frequency.

$$$$X = 2\pi fL$$$$ Where:

L = coil inductance in Henrys

f = frequency

X = impedance

Your contactor's coil is specified at 50-60Hz. If you instead use 240Hz, then the impedance will be higher, and not enough current will flow through the coil to activate it.

X above can be substituted as R in Ohms law V=IR => V=IX to show how much current will flow.