Alarm system

摘要

An alarm system for alarming whenever there is a power leakage from an electronic device, includes a voltage decreasing circuit, a switch circuit and an alarm circuit. The voltage decreasing circuit receives a first voltage from a live wire output terminal and outputs a second voltage. The switch circuit outputs a control signal when the power leakage is detected. The switch circuit is electrically connected to a connection port. The connection port is electrically connected to the live wire output terminal and a neutral wire output terminal. The alarm circuit receives the control signal and alarms. If there is power leakage from the electronic device, the first voltage from the live wire input terminal flows into the ground wire input terminal via the electronic device; the switch circuit turns on and the alarm circuit is closed to alarm.

主权项

1. An alarm system for alarming when there is a power leakage from an electronic device, comprising:
a voltage decreasing circuit adapted to receive a first voltage from a live wire output terminal and output a second voltage; a switch circuit adapted to output a control signal when the power leakage is detected; wherein the switch circuit is electrically connected to a connection port; the connection port is electrically connected to the live wire output terminal and a neutral wire output terminal; and an alarm circuit adapted to receive the control signal and alarms; wherein the second voltage is provided to the alarm circuit; the connection port is electrically connected to the electronic device to provide power supply for the electronic device; wherein the voltage decreasing circuit comprises a first resistor, a zener diode, and a capacitor; the first resistor comprises a first resistor first terminal and a first resistor second terminal; the zener diode comprises a zener diode anode and a zener diode cathode; the first resistor first terminal is electrically connected to the live wire output terminal for receiving the first voltage; the first resistor second terminal is electrically connected to the zener diode anode; the zener diode cathode is adapted to output the second voltage; the zener diode cathode is electrically connected to the neutral wire output terminal via the capacitor; the switch circuit comprises a second resistor and a transistor; the connection port comprises a live wire input terminal, a neutral wire input terminal and a ground wire input terminal; the second resistor comprises a second resistor first terminal and a second resistor second terminal; the transistor comprises a transistor base, a transistor emitter and a transistor collector; the second resistor first terminal is electrically connected to the ground wire input terminal; the second resistor second terminal is electrically connected to the transistor base; the transistor collector is electrically connected to a connection point between the zener diode and the capacitor; and the transistor emitter is adapted to output the control signal.