4-2 Function Mode Output frequency A067 A068 A068 A066 A065 A066 A063 A064 A064 Frequency reference PID Function 4 This function enables process control of such elements as flow rate, air volume, and pressure. Functions •To use this function, set A071 to 01. •To switch between enable/disable via the terminal block (external signal), allocate 23 (PID enable/ disable) to the desired multi-function input. Select OFF for enable and ON for disable. „ Basic Structure of PID Control (Example) Control value s T s T K d i p 1 1 Target value 0 to 10 V 4 to 20 mA fs M = + - Deviation ε + · · + 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 4-20 Parameter No. Function name Data Default setting Unit A071 PID selection 00: Disabled 01: Enabled 00 ⎯ A072 PID P gain 0.2 to 5.0 1.0 ⎯ A073 PID I gain 0.0 to 150.0 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 01: FV 02: RS485 communication 03: 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 0.00 to 100.0 0.0 % 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, C001 to C005, C021, C026