User Manual
E727T0005, valid for E-727
BRO, 2019-06-28
Physik Instrumente (PI) GmbH & Co. KG, Auf der Roemerstrasse 1, 76228 Karlsruhe, Germany
Page 55 / 240
Phone +49 721 4846-0, Fax +49 721 4846-1019, Email
The values for position and output voltage should follow the commanded open-loop
values: The axis position should always correspond approximately to the commanded
value, and the output voltage(s) should become noticeably different from 0 V and then go
back to zero again during the procedure (with the E-727, the output voltage range is -30 to
+130 V; the output voltage(s) corresponding to a given open-loop value depend(s) on the
connected stage(s)).
In the example shown in the figure above, the open-loop value for axis 1 was increased to
30 by clicking the
>
button three times (step size value is 10). The current position
approximately corresponds to the commanded open-loop value (29.167 µm). Because
axis 1 of the stage is driven by two piezo actuators in the example, the output voltage of
the corresponding output signal channels 1 and 2 has changed to appropriate values.
2.
Make open-loop frequency response measurements in the
Piezo Dynamic Tuner
window of
PIMikroMove to determine the resonant frequencies of the axes. See "Servo Controller
Dynamic Tuning" (p. 134) for more information.
If there are resonances which are intolerable in your application:
−
Adjust the notch filter settings for the axis before you switch to closed-loop operation
for the first time (servo on). Furthermore, it might be necessary to readjust the preset
servo parameters for the axis.