most conventional induction motors are most efficient at about 5% above rated voltage. If you continue to increase the voltage, the iron saturates and the current goes up very fast. in the case mentioned the current will be several times the rated current and if you are lucky and the correct...
an alternative to the use of the magnetic blowout for DC loads would be to connect a diode across the contacts. this diode should be connected so that it does not conduct current when the contact is open. when the contact opens with an inductive load, the voltage is reversed across the diode...
