8 Adjustment of Internal Settings
46
Version: 2.0.0
PZ166E
E-625 Piezo Servo Controller
8.5.2
Setting the P-I Controller in Analog Mode
Requirements
You have correctly adjusted the notch filter (p. 43).
You have not changed anything on the system setup that was used for the adjustment
of the notch filter.
All devices are still ready for operation.
Tools and Accessories
As for the adjustment of the notch filter (p. 43)
Setting the P-I Controller
1.
Switch the servo mode on by moving switch 3 on the
Settings
DIP switch block to ON
(down).
If an oscillation (positioner's humming) can be heard after switching on the servo mode:
a)
Switch the servo mode off immediately.
b)
Adjust the P term for the P-I controller by turning the P2 potentiometer on the
E-802.55 servo controller submodule with the trimmer adjustment tool fully
counterclockwise.
Typically you will hear a click.
c)
Switch the servo mode on again.
2.
Generate a 5-V square wave signal (peak-peak) with 5 to 10 Hz using the function
generator.
3.
On the oscilloscope, observe the step response of the positioner (sensor monitor signal
over time).
4.
Alternatingly turn P2 and P3 (I term) potentiometers on the E-802.55 servo controller
submodule using the trimmer adjustment tool until the step response is optimal
(minimal overshot, settling time not too long).
5.
Disconnect the E-625 from the power source by removing the power cord of the wide
input range power supply from the power socket.
6.
Close the E-625.
The two figures below have examples for step response measurements with a digital storage
oscilloscope for improvement of the P-I controller. The input voltage and the sensor signal are
shown.
