Abstract: Control circuit for electromagnet with two coils used to determine a call phase and a hold phase, and powered from a DC power source. The energy source comprises a current generator and a capacitor powered by this current generator. A control device controls two switches, in which the first switch controls discharge of the capacitor in the first coil during the call phase, and the second switch sets up current passing through a second coil during the call phase and the hold phase. The required current output from the current generator is thus reduced.

Abstract: Apparatus for controlling an inductive load, particularly for a coil of an electromagnet, including an electronic chopper switch fitted in series with the coil and controlled by a pulse width modulator, and an opening switch, also fitted in series with the coil. A transformer converter 20 with two secondary windings, one of which is connected to the modulator 11, and the other is connected to the gate of the opening transistor T2 via a switch 25 solicited by the opening signal.

Abstract: Device designed to control a coil forming part of a solenoid valve, for example in a contactor type device.A switching power supply 14 includes a winding S1 powering a control circuit 15 and another winding S2 placed with a switch T2 at the coil terminals. Switch T2 is controlled by the control circuit to power the coil in the hold phase starting from the switching power supply. This reduces disturbances during the hold phase.