PI PiezoWalk E-712 - Page 13

User Manual
E712T0010, valid for E-712.N1, E-712.1AM, E-712.1AN, .2AN, .3AN
CMo, BRo, 10/31/2024
Physik Instrumente (PI) SE & Co. KG, Auf der Römerstraße 1, 76228 Karlsruhe, Germany page 13 / 40
Phone +49 721 4846-0, fax +49 721 4846-1019, e-mail info@pi.ws, www.pi.ws
The following parameters are used for the iterative relax procedure:
 Driving Factor Of Piezo (0x09000000) and Position From Sensor (0x07000500) are used to detect if the
axis is driven by one PiezoWalk® drive and measured by one sensor only.
 On Target Tolerance (0x07000900): See the figure on p. 14.
 PiezoWalk Open-Loop Velocity (0x07000204). Is used to calculate the piezo voltage slew rate and thus
determines the duration of the involved simple relax procedure.
 Optional: The Time To Relax PiezoWalk Channel parameter (0x07012800) can be used to specify the
duration of the involved simple relax procedure directly in s. Default is 0, which means that the duration
of the involved simple relax procedure depends on the PiezoWalk Open-Loop Velocity setting.
 Max Special Relax Process Time (0x07031000) limits the total duration of the iterative relax procedure.
Default: 2 s
 Special Relax Type (0x07031100) selects the driving mode for the closed-loop part of the iterative relax
procedure. 2 = analog mode (default), 1 = nanostepping mode
 Special Relax Process Gain (0x07030f00) specifies a gain value. Change the default value only after
consultation with PI!
 Parameters for a subsequent creep reduction procedure for NEXLINE® drives: see p. 15
Further requirements and restrictions:
1. A position sensor must be present for the axis, and the servo parameters of the axis must be set
properly.
2. The shearing components of both pairs of piezo actuators must be assigned to separate piezo amplifier
channels (default).
3. The maximum number of iterations is 20.
INFORMATION
If the iterative relax procedure is not finished successfully, this will result in a high position error. In this case,
you can adjust the following settings:
 Increase the value of the Max Special Relax Process Time parameter (ID 0x07031000).
 Optimize the duration of the included simple relax procedure. You can do this either by increasing the
value of the PiezoWalk Open-Loop Velocity parameter (0x07000204) and reducing the value of the
Servo-Loop I-Term parameter (0x07000301) which is used for the analog mode motion, or by directly
specifying the duration of the simple relax procedure via the Time To Relax PiezoWalk Channel
parameter (ID 0x07012800).
 By default, the closed-loop part of the iterative relax procedure is executed via motion in analog mode.
Via the Special Relax Type parameter (ID 0x07031100), you can specify that this motion is executed in
closed-loop nanostepping mode instead.