Mitsubishi FR-E 500 Instruction Manual page 154

( 5 ) Parameter setting
Parameter
Setting
Number
0
128 20
21
0.1 to
1000%
129
9999
0.1 to
130 3600 s
9999
0 to 100%
131
9999
0 to 100%
132
9999
133 0 to 100%
0.01 to
10.00 s
134
9999
( 6 ) Adjustment procedure
Parameter setting
Terminal setting
Name
No PID action
PID
action For heating, pressure control, etc. PID reverse action
selection
For cooling, etc.
If the proportional band is narrow (parameter setting
is small), the manipulated variable varies greatly
PID
with a slight change of the process value. Hence, as
the proportional band narrows, the response
propor-
sensitivity
tional
deteriorates, e.g. hunting occurs.
band
Gain Kp = 1/proportional band
No proportional control
Time required for the integral (I) action to provide
the same manipulated variable as that for the
PID
proportional (P) action. As the integral time
integral
decreases, the set point is reached earlier but
time
hunting occurs more easily.
No integral control.
Set the upper limit. If the feedback value exceeds
the setting, the FUP signal is output. (Process value
Upper
of 4mA is equivalent to 0% and 20mA to 100%.)
limit
No function
Set the lower limit. (If the process value goes out of
the setting range, an alarm can be output. In this
Lower
case, the process value of 4mA is equivalent to 0%
limit
and 20mA to 100%.)
No function
Only valid for the PU command in the PU operation
PID
or PU/external combined operation mode.
action set
For external operation, the voltage across 2-5 is the
point for
set point.
PU
(Pr. 902 value is equivalent to 0% and Pr. 903 value
operation
to 100%.)
Time required for the differential (D) action to provide
the same process value as that for the proportional
PID
(P) action. As the differential time increases, greater
differential
response is made to a deviation change.
time
No differential control.
Adjust the PID control parameters, Pr. 128 to Pr. 134.
Set the output terminal functions, Pr. 190 to Pr. 192.
Run
Description
(gain) improves
139
PARAMETERS
PID forward action
but the stability