Abstract
This paper introduces the domestic electrical fault diagnosis system design, as well as existing problems, and introduced a programmable controller at the same time the working principle of selection basis. A PLC-based design of the electrical fault diagnosis system design, detail on the choice of Siemens S7-200 PLC and the same type of S7-300 S7-400PLC, according to the design requirements of the input and output of the PLC I / O for distribution, and preparation of the ladder diagram system operation. Prepared to boot, press the button after boot, the first detection circuit breaker status, if the initial state for closed circuit breakers, electrical not start, and sound and light alarm. If the circuit breaker to disconnect the initial state, the circuit breaker reclosing, the electrical start. Start in the process, if a failure occurred, the protection PLC corresponding action. Start after the completion of "motor on / off indicator light"-liang, the electrical normal operation. Running process, PLC followed by motor cycle test whether there has been a phase short circuit, breaking phase, low-voltage, single-phase - to-ground, overload, over-current fault, and so, if occurred, PLC protection action accordingly. Shutdown, PLC received shutdown orders, tripping circuit breakers, "Motor on / off indicator light" eliminate. Fault sound and light alarm at the "Alarm reset button" reset. This choice is based on the design of the motor PLC fault diagnosis system design.