Abstract:
Innovative damage detection in a safe counter circuit with a windowed comparator. The proposed method includes A digital counter technique designed in a safe error mode for lowspeed detection and the use of a band-pass filter in combination with booster circuit To be used as a self-check function of the counter for detecting abnormalities of the internal signal of the system itself. The normal output voltage signal appears only when The speed of the motor is lower than the rated value. including the counter circuit and all parts of the connecting device must work normally. If, in addition to the above cases, no signal appears on the output side, the counter circuit has been added to a window comparator. For use in checking the displayed pressure range. This is to monitor the operation and confirm the working condition of the counter circuit in safe operating mode. The circuit is applied to the safety function for the use of electric motor drive systems defined in accordance with IEC 61800-5-2. The digital counter is used with the safe speed range tracking function. And the window comparator circuit is used with the safe speed range limiting function. The motor speed test range is 1-1,500 rpm. The digital counter circuit will cut off at 1206 rpm, resulting in the high frequency signal (f4) not appearing and the window comparator circuit will cut off at 904 rpm, causing the force. The output pressure does not appear by the circuit either. All were analyzed for safety by using Failure Mode and Effect Analysis (FMEA ) in safety systems.