4-2 Function Mode PID Function •This function enables process control of such elements as flow rate, air volume, and pressure. 4 Functions •To use this function, set A071 to "01" or "02". •You can disable the PID operation in progress using an external signal. To use this function, allocate "23" (PID: PID disabled) to any of the multi-function inputs. While the PID terminal is turned on, the Inverter disables the PID function and outputs normally. •You can limit the PID output under various conditions.
„ Basic Structure of PID Control (Example) Feedforward Disabled 0 to 10 V 4 to 20 mA -10 to 10 V Target value 0 to 10 V 4 to 20 mA fs M + - Deviation ε s Td s T Kp i 1 1 + + Control volume + - Normal control of the Inverter Sensor Feedback 0 to 10 V 4 to 20 mA Transducer Kp: Proportional gain Ti: Integral time Td: Derivative time s: Operator ε : Deviation 4-31 Parameter No. Function name Data Default setting Unit A071 PID selection 00: Disabled 01: Enabled 02: Reverse output enabled 00 A072 PID P gain 0.2 to 5.0 1.0 A073 PID I gain 0.0 to 3600.0 1.0 s A074 PID D gain 0.00 to 100.0 0.0 s A075 PID scale 0.01 to 99.99 1.00 Time A076 PID feedback selection 00: FI-FC (4 to 20 mA) 01:
FV-FC (0 to 10 V) 02: RS485 communication 03: Pulse train frequency 10: Operation function output 00 A077 Reverse PID function 00: Deviation = Target value - Feedback value 01: Deviation = Feedback value - Target value 00 A078 PID output limit function 0.0 to 100.0 0.0 % A079 PID feedforward selection 00: Disabled 01: FV-FC (0 to 10 V) 02: FI-FC (4 to 20 mA) 03: FE-FC (-10 to 10 V) 00 C044 PID deviation excessive level 0. to 100. 3.0 % C052 PID FB upper limit 0.0 to 100.0 100 % C053 PID FB lower limit 0.0 % Related functions d004, A001, A005, A006, C001 to C008, C021 to C025