Pid On/Off And Pid Clear - Hitachi L300P Series Instruction Manual

PID ON/OFF
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
and PID Clear
PID loop execution via an intelligent input terminal. It overrides the parameter A071 (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 A071=01.
The PID Clear function forces the PID loop integrator sum = 0. So, when you turn ON an intel-
ligent 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.
Valid for
inputs:
Required
settings:
Notes:
• The use of [PID] and [PIDC] terminals are
• Do not enable/disable PID control while the
• Do not turn ON the [PIDC] input while the
Opt.
Symbol Function Name
Code
23 PID PID Disable
24 PIDC PID Clear
C001, C002, C003, C004,
C005
A071
optional. Use A071=01 if you want PID loop
control enabled all the time.
motor is running (inverter is in Run Mode).
motor is running (inverter is in Run Mode).
L300P Inverter
Input
Description
State
ON Disables PID loop execution
OFF Allows PID loop execution if A71=01
ON Force the value of the integrator to zero
OFF No change to PID loop execution
Example: (Requires input configuration—
see page 3–43. Jumper position shown is
for –xFU/-xFR models; for –xFE models,
see page 4–11.)
PIDC PID
TH FW
5
P24 PLC CM1
See I/O specs on page 4–8.
4–29
4 3 2 1