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CHAPTER 6 - DETAILED PARAMETER DESCRIPTION
Range
[Factory Setting]
Parameter
Unit
Description / Notes
Some examples of initial settings of the PID Regulator Gains and PID
Ramp Times for some applications mentioned in item 6.5.1, are shown
in table 6.65.
P520
0.000 to 7.999
PID Proportional
[ 1.000 ]
Gain
0.001
P521
0.000 to 7.999
PID Integral Gain
[ 0.043 ]
0.001
P522
0.000 to 3.499
PID Differential
[ 0.000 ]
Gain
0.001
P523
0.0 to 999
PID Ramp Time
[ 3.0 ]
0.1 s (< 99.9 s)
1 s (> 99.9 s)
Magnitude
Pressure pneumatic
system
Flow pneumatic
system
Pressure hydraulic
system
Flow hydraulic
system
Temperature
Level
Proportional
P520
1
1
1
1
2
1
Integral
P521
0.043
0.037
0.043
0.037
0.004
Refer to note
(2)
Derivative
P522
0.000
0.000
0.000
0.000
0.000
0.000
PID Ramp
Time
P523
3.0
3.0
3.0
3.0
3.0
3.0
Action Type
P527
0 = Direct
0 = Direct
0 = Direct
0 = Direct
Refer to note
(1)
Refer to note
(1)
Gains
Table 6.65
- Suggestions for gain settings of the PID regulator
(1)
For temperature and level control, the action type will depend
on the process. For instance, in the level control, when the
inverter drives the motor that removes fluid from a tank, the action
will be contrary as when the inverter drives the motor that fills a
tank and thus the fluid level increases and the inverter should
increase the motor speed to lower the fluid level, otherwise the
inverter action that drives the pump motor to pump fluid into the
tank will be direct.
(2)
In case of level control, the setting of the integral gain will depend
on the time required to fill the tank from the minimum acceptable
level up the desired level, in the following conditions:
I. For the direct action, the time should be measured by
considering the maximum input flow and the minimum output
flow.
II. In the inverse action, the time should be measured by
considering the minimum input flow and the maximum output
flow.
The equation to calculate an initial value for P521 (PID Integral Gain) as
a function of the system response time, is presented below:
P521 = 0.02 / t
t = time (seconds)
P524
(1)
0 or 1
Selection of the
[ 0 ]
PID Feedback
-
It selects the feedback input (Process Variable) of the PID regulator:
P524
AIx
0
AI2 (P237 to P240)
1
AI3 (P241 to P244)
Table 6.66
- Feedback selection
NOTES!
