THORLABS K-Cube Piezo Controller User Manual page 49

6.2.2 Control Tab
Feedback Loop Settings
Loop mode - This panel can be used to select between the two distinct
operating modes: open loop and closed loop. Note that closed loop operation
is only possible if an external position reader (such as the TGS001 Strain
Gauge Reader) is used in conjunction with the piezo cube.
If the Piezo Driver is switch to closed loop mode without being connected
to a Strain Gauge Reader, the piezo driver will expect a feedback signal
and the piezo drive voltage will ramp up to the maximum limit. If the limit
is set to 75V, a protective circuit limits the voltage to 75V. If 100V or 150V
When the K-Cube Piezo Driver is used in conjunction with the K-Cube Strain Gauge
Reader unit (KSG101) on the K-Cube Controller Hub (TCH002), high precision closed
loop operation is possible using the complete range of feedback equipped piezo
actuators available from Thorlabs.
Select Open Loop or Closed Loop as required.
When the KPZ101 and KSG101 are used in closed loop, the joystick wheel
on the top panel of the unit controls the position setpoint rather than
voltage. This position setpoint is a percentage (0-100%) reflecting min-
max piezo extension, e.g. for a 30 micron piezo stack, a position setpoint
of 50% equates to 15 micron. Further, when operating in closed loop
mode, if you click the 'Set' button on the GUI of the KPZ101 you are
prompted to enter a 'Position Setpoint [0-100%] - see Fig. 6.2 below.
Fig. 6.1 Piezo Settings panel
Caution
is selected, the output will ramp to 150V.
Note
K-Cube Piezo Driver
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