Slave and hot-wire perception type load control system null of hot-wire perception type load control

摘要

PROBLEM TO BE SOLVED: To provide a heat ray sensing load control system, which sets a detection area at plural points and changes the control state of a load according as which detection area a human body is detected in, by relatively easy wiring and at a relatively low cost. SOLUTION: The slave machine 3 is equipped with two pairs of connection terminals T1 and T2 which connect each separate signal line between itself and two master machines. When a sensor circuit IR detects a human body, a transistor Q1 is turned on and, by lowering a voltage applied to the connection terminal T1 through the signal line from one of the master machines down to a breakover voltage of a Zener diode ZD1, a load control signal is transmitted to one of the master machines. Also, when the transistor Q1 is turned on, a photo coupler PC1 is turned on and the load control signal is transmitted to the other master machine by lowering the voltage applied to the connection terminal 2 through the signal line from the other master machine down to a breakover voltage of a Zener diode ZD2.