THORLABS K-Cube Piezo Controller User Manual page 59

closed loop control but in this case the KSG101 MONITOR output must be
connected to the KPZ101 EXT IN input using an external SMA to SMA cable.
As mentioned in the previous section, the function of the analogue input
source depends on whether the cube is used in open or closed loop
mode. In open loop mode, the input selected here will be added to the
Drive Input Source if the 'External Input' is enabled in this panel. In closed
loop mode, the input selected here expects to see the feedback input
.
Channel 2
Bay 1
Channel 1
Feedback Loop Settings
Loop mode - This panel can be used to sel ect 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. Switching the unit over to clo sed loop mode when
there is no position feedback signal connected can result in the feedback loop
ramping the output voltage up to its maximum value.
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 (KCHx01), high precision closed
loop operation is possib le using the comple te range of feedback equipped piezo
actuators available from Thorlabs.
Select Open Loop or Closed Loop as required.
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
from the external position reader.
Channel 2
Bay 2 Bay 3
Fig. 6.2 Controller Hub Feedback Channels
Caution
is selected, the output will ramp to 150V.
Note
Bay 4 Bay 5
K-Cube Piezo Driver
Channel 2
Bay 6
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