Ac control supply to DC contactor and vice versa

What will happen If i give ac control supply to dc contactor or relay and viceversa.

AC on a DC coil will result in a vibrating buzzer. The coil will not hold in. DC on an AC coil will pull in properly but the DC voltage would have to be much less than the AC voltage because the DC resistance of the coil is much less than the AC impedance at 50 or 60hz.

This app note may be of some use to you:



-rpoet

From personal experience, DC on an AC coil will pull the contactor in for just long enough to give the panel a thorough test, sign it off as OK, crate it up and send it to the client.

It will fail very soon after that