Pid On/Off And Pid Clear - Hitachi WJ200 Series Instruction Manual

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PID ON/OFF and PID Clear

The PID loop function is useful for controlling motor speed to achieve constant flow,
pressure, temperature, etc. in many process applications. The PID Disable function
temporarily suspends PID loop execution via an intelligent input terminal. It overrides
the parameter
frequency output characteristics. The use of PID Disable on an intelligent input
terminal is optional. Of course, any use of the PID loop control requires setting PID
Enable function A071=01.
The PID Clear function forces the PID loop integrator sum = 0. So, when you turn ON
an intelligent input configured as [PIDC], the integrator sum is reset to zero. This is
useful when switching from manual control to PID loop control and the motor is
stopped.
CAUTION: Be careful not to turn PID Clear ON and reset the integrator sum when the
inverter is in Run Mode (output to motor is ON). Otherwise, this could cause the motor
to decelerate rapidly, resulting in a trip.
Option Terminal
Code Symbol
PID
23
PIDC
24
Valid for inputs:
Required settings
Notes:
• The use of [PID] and [PIDC] terminals are
optional. Use A071=01
control enabled all the time.
• Do not enable/disable PID control while the motor
is running (inverter is in Run Mode).
• Do not turn ON the [PIDC] input while the motor is
running (inverter is in Run Mode).
(PID Enable) to stop PID execution and return to normal motor
A071
Function Name State
PID Disable
PID Clear
C001~C007
A071
if you want PID loop
ON Disables PID loop execution
OFF Allows PID loop execution
ON Force the value of the integrator to zero
OFF No change in PID loop execution
Example (default input configuration shown):
7 6 5
See I/O specs on chapter
Description
PIDC PID
4 3 2 1 L
PLC PCS
4.
P24