Panasonic FP7 Series Command Reference Manual page 501

Conversion formula: (Output upper limit - Output lower limit) x (Internal calculated value) /
10000 + (Output lower limit)
● If [S4] is allocated to a hold type area, the manipulated value (MV) is retained even if the
execution condition of the EZPID instruction is switched OFF.
● OUT is not necessary after EZPID instruction using analog output. Additionally, PWM is
output OFF in this situation.
■
Setting of auto-tuning bias value [S4+6]
● If it is necessary to control output during auto-tuning (e.g. prevent overheating), set, as a bias
value, the difference between the actual set point value (SP) during PID control operation
and the set point value (SP') during auto-tuning.
● In the case of reverse operation (heating), (SP) is equal to or larger than (SP') and the
difference thereof is given as the bias value.
● In the case of forward operation (cooling), (SP) is equal to or smaller than (SP') and the
difference thereof is given as the bias value.
● Even if auto-tuning is started up, with the process value (PV) located near the set point value
(SP), auto-tuning is executed using the set point value (SP') adjusted with the bias value.
Temperature
Set point
value (SP)
(SP')
WUME-FP7CPUPGR-12
10.12 EZPID (PID Operation: PWM Output Available)
Auto-tuning offset value
Auto-tuning PID control
Calculate Kp, Ti and Td
Auto-tuning in
reverse operation
Time
10-51