JPS6489891A - Load controller - Google Patents

Abstract

PURPOSE:To prevent the power control signal output means of a slave equipment from being destroyed by outputting a short-circuit signal with the aid of a short-circuit detection means when short-circuit occurs between a load circuit and the power control signal output means and stopping the output of the slave equipment with the aid of the control means of a master equipment. CONSTITUTION:When the short-circuit occurs between the illumination load circuit 28 and a dimming signal output means 17, the short-circuit signal is outputted to the control means 4 of a main operation board 1 through a transmission interface 12 by conducting a Zener diode 32, lighting a light emitting diode 34 and turning on a phototransistor 35. The control part 4 turns off the light emitting diode 19 of the short-circuit channel of a dimming control signal generation part 16 of a signal terminal unit 3 when the short-circuit signal is inputted. Thus the output is stopped and the output from the dimming control signal output means 17 of the corresponding channel is stopped. Simultaneously, a light emitting diode 9 corresponding to the short-circuit channel is lighted to the address display part 9 of the signal terminal equipment 3 having the short-circuit channel.