a stepping motor is described having two operative modes , the first mode being a normal rotary mode and the second a stationary mode . during rotary operation , the induced energy created by interruption of the current flow through the energized phase winding is dissipated quickly by a zener diode connected across the winding . in the stationary mode , a pulsed current is fed to one of the phase windings of the motor to assure stationary positioning of the rotor . during stationary operation , the zener diode is shunted with a second conventional diode providing a low impedance path to the current induced in the phase winding upon de - energization . this low impedance path greatly reduces the energy dissipated during the off condition of the pulsed current thereby greatly reducing motor power requirements during stationary operation .