| 摘要 |
PURPOSE:To prevent an electromagnetic switch from microoscillation within a short time and to prolong the life of the switch at its contact by setting up limit bands of manipulated variable on the upper and lower limits of a proportional band. CONSTITUTION:A proportional band is set up so that the manipulated variable of a load is proportional to the deviation between the set point and detected point of temperature, on/off pulse outputs are used as output format and the time ratio of on to off is set up so as to be proportional to the deviation. In this situation, the limit bands of manipulated variable are set up on the upper and lower limits of said proportional band, and the output off time and output on time are limited so as to not to be dropped less than a fixed time in the lower limit band of the manipulated variable and exceeded more than the fixed time in the upper limit band respectively. |
