What happens if the 220v contactor is mistakenly connected to the 380v?

- Jul 18, 2019-

High voltage: Normal suction, but the coil will burn out in a moment.

Low voltage: do not absorb, some will hum (cannot suck), but will not burn the coil.

On the construction site, it is often the case that a low rated voltage (e.g. 127V) AC contactor coil is connected to a high supply voltage (e.g. 220V, 380V) or a high rated voltage (e.g. 380V) electromagnetic coil to a low supply voltage (e.g. 220V, 127V).

These two misconnections, whether voltage or high or low, produce the same result of coil burn-out.

It is not difficult to understand that the low voltage coil misconnects the high voltage and burns because the magnetic current is too large, but why does the high voltage coil burn down by mistake to the low supply voltage? The reason is that the electromagnetic coil magnetic voltage is not enough, can not produce enough suction force to close the title iron. And the title iron for a long time in the atmospheric gap jitter, the magnetic resistance is so large that the coil inductive capacity is greatly reduced, so that the coil for a long time in a low impedance high current state, until burned.