THORLABS LNR502E, User Manual

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Rev A Apr 2020
Page 21
Chapter 6 Operating Legacy Units
1) Run the APTUser utility. On the main motor graphical panel an 'Encoder' button is displayed at the bottom left of the panel.
Fig. 6.2 Motor GUI panel with encoder button
2) Click the 'Encoder' button to display the 'Encoder Control Panel'.
This panel is used to enable/disable encoder position feedback control and to alter the modes of operation when encoder
control is enabled.
Positioning Mode
MicroStep Positioning
- By default the software is set to 'Microstep Positioning' mode. In this mode, all position displays and motor
moves are based on positions derived from the internal microstep counters within the controller (i.e. are not based on the encoder
count).
For example, the APT system can control to a resolution of 409600 microsteps per revolution. For a stage or actuator with a
1 mm pitch lead screw, the controller will generate 409600 microsteps to move 1 mm. To display position values, the software
converts the microstep count into a 'real world' position by dividing by 409600.
Encoder Positioning -
If 'Encoder Positioning' is selected, other controls on the panel become available
.
In this mode, the position displays on the GUI panel, and all motor moves, are based on positions derived from the encoder system
fitted to the stage/actuator. So for example, the encoders currently fitted to our stages are set to 10000 counts per mm (i.e.
0.1micron per count). To move 1 mm, the controller will drive out the appropriate number of microsteps to result in an encoder count