8.3.12
RFB limiter function
The RFB (reset feed back) function operates when deviation (E) continues for a long period of time. In such an
occasion, this function limits the PID operation result (manipulated value (MV)) from an integral action so that it does
not exceed the valid range of the manipulated value (MV).
This function operates automatically on execution of PID control; therefore, a setting by the user is unnecessary.
Remark
When the PID operation result exceeds the upper limit output limiter value, the temperature control module operates as
follows:
• The RFB function levels the manipulated value (MV) to the upper limit output limiter value by feeding back the
exceeded value to the integral value.
When the PID operation result is below the lower limit output limiter value, the temperature control module operates as
follows:
• The RFB function levels the manipulated value (MV) to the lower limit output limiter value by feeding back the
lacking value to the integral value.
180
Heating-cooling
Standard