LED DEVICE FOR DISCRIMINATING OPERATION OF EMERGENCY SAFETY SWITCH

摘要

PURPOSE: An LED device is provided to discriminate emergency switch operation in an easy manner in a shortest time period by arranging a combination of a resistance and an LED which operates at a voltage and current lower than those of the relay. CONSTITUTION: An LED device comprises a combination of an LED(2) which operates a weak voltage(0.5V to 3V) and current(1mA to 20mA), and a resistance(3) made up of a voltage lower than a relay driving voltage. Since the LED adopting a two-wire system turns off at a voltage lower than that of a relay(4), the LED turns off at a contact point closed state and turns on by the supplied DC power at a contact point open state where the circuit is disconnected by the operation of emergency switch.