Hitachi WJ200-001L, Instruction Manual

Page: 239 / 680

4

32
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

(PID Enable) to stop PID execution and return to normal motor
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

=

.
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
Code
Terminal
Symbol
Function Name State Description

PID PID Disable ON Disables PID loop execution
OFF Allows PID loop execution

PIDC PID Clear ON Force the value of the integrator to zero
OFF No change in PID loop execution
Valid for inputs:

~

Example (default input configuration shown):
See I/O specs on chapter 4
.
Required settings

Notes:

The use of [PID] and [PIDC] terminals are
optional. Use

=

if you want PID loop
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).
PIDC PID
7 6 5 4 3 2 1 L P24
PLC