Introduction to the automatic detection and fault diagnosis of PLC

PLC has a perfect self-diagnosis function, such as failure, with the help of the diagnostic program can easily find the failure parts, you can resume normal work after replacement. Fault handling methods can see troubleshooting guide of PLC controller system manual. Practice has proved that the external equipment failure rate is much higher than the PLC, and the equipment failure, the PLC controller will not automatically stop, can make the fault scope. In order to find fault in time, the trapezoidal chart procedure realize fault self diagnosis and the treatment. 1. Timeout detection equipment in each work step of the time required to basically remain unchanged, therefore time can be used as a reference, in programmable controller sends a signal to the corresponding external actuator start activity began to devise, starting a timer timer value is longer than under normal circumstances the duration of the action around 20%. As an actuator in the run normally after 10 s, make the limit switch action, signaling the end of the action. Began in the actuator moves in the starting value of 12 s, if after 12 s haven't received the signal the end of the action, made by timer normally open contacts of the fault signal, the signal to stop normal procedures, starting alarm and fault display program, and ensure that operators and maintenance personnel can quickly distinguish the types of fault, troubleshooting measures in a timely manner. 2. Logic error checking in the normal operation of system, PLC controller input and output signal and the internal signal ( Such as memory for state) There is a definite relationship between each other, such as the logic of abnormal signal, then broke down. So you can prepare some common faults of abnormal logical relationship, once the abnormal logical relationship is ON state, should according to the fault handling. Such as mechanical movement has had two limit switch action, in the process of the two signals do not connected at the same time. If they are connected at the same time, shows that at least one limit switch is stuck, should stop processing. In ladder diagram, with the two limit switch corresponds to the memory of a normally open contact in series, said to drive a fault memory of a limit switch can be tested.
Shenzhen Coolmay Technology Co., Ltd. is different from other companies as we provide timely and unique services to our respected clients.
As manufacturers we are determined to be the very best in plc manufacturers, regardless of the size, pedigree or inclinations of our competitors.
plc manufacturers provider at Coolmay PLC offers a wide variety of in many options. quality is absolutely ensured if you choose us. welcome to visit our factory.