| 摘要 |
PROBLEM TO BE SOLVED: To prevent the short-circuited output between motor drive inverter devices caused by phase deviation and to make it possible to prevent the stop of the entire system by a fault by detecting the abnormal output in communication based on the difference between the signal interval of the pulses based on the phase angle of phase data and the signal interval of the output frequency data. SOLUTION: The devices performing the following functions are provided, and the communication abnormality detecting circuit is constituted. A converter 536 uses especially the communication paths of two systems effectively and obtains the time conversion value from the output frequency data of the output of one receiver RX1. A reading device 531' and a timer 532' load the value of a timer at a leading edge from the phase data of the output of another receiver RX2. A difference device 533' obtains the difference between the output of the reading device and a memory output. A comparator 535' detects the presence or absence of the pulse signal of the output of the difference device for every period of the output of the converter and generates the signal of the communication abnormal output only when the reception is not performed. Then, the pulse signal of the phase data is detected at every conversion period of the output frequency data, and the receiving check at the normal interval is performed. |
