Frequency Search; Dynamic Frequency Search - THORLABS ELL6 Operating Manual

ELL6K Dual Position Optics Slider Kit
4.3.

Frequency Search

Due to load, build tolerances and other mechanical variances, the default resonating frequency of a particular
motor may not be that which delivers best performance. A frequency search can be performed using the Main
GUI panel in the ELLO software, or by using the serial communication line (SEARCHFREQ_MOTORX message),
which offers a way to optimize the operating frequencies for backward and forward movement.
This search can also be performed manually as follows:
With the remote handset
1. Press and hold BW button.
2. Power up the slider.
3. The slider performs a self-test by moving from one position to the other. If the slider does not move or
complete, move the slider manually from one end of travel to the other until it is no longer attempting to
move.
Note: The BW button must be held down during manual actuation.
4. Release the BW button. The red INM LED should be lit briefly.
5. A frequency search will now be performed. To avoid overheating the motor, a pause of 1 second is
programmed after each move. The red INM LED will be lit after each movement
6. Press and hold the BW button until red INM LED turns ON and then OFF, and the slider stops moving.
The optimized resonating frequency is stored until the next frequency search is requested.
7. Power down the slider.
8. Wait for the green PWR LED to turn OFF.
9. Power up the slider. The device will now complete a self test.
Without the remote handset
1. Connect Pin 6 of connector J2 to 0V.
2. With J2 Pin 6 connected to 0V, power up the slider.
3. The slider performs a self-test by moving from one position to the other. If the slider does not move or
complete, then move the slider manually from one end of travel to the other until it is no longer attempting
to move.
Note: J2 Pin6 will need to be shorted to 0V during manual actuation.
4. Connect J2 Pin 6 to 3.3V.
5. A frequency search will now be performed. To avoid overheating the motor, a pause of 1 second is
programmed after each move.
6. Connect J2 Pin 6 to 0V. The slider stops moving and the optimized resonating frequency is stored until
the next frequency search is requested.
7. Power down the slider
8. Wait for 2 seconds for power supply line to go to 0V.
9. Power up the slider. The device will now complete a self test.

4.3.1. Dynamic Frequency Search

The ELL6 unit also incorporates a dynamic frequency search. After the initial frequency search detailed above has
been performed, the ELL6 unit will search for the best mechanical performance every time the slider is moved,
tracking performance against temperature drift and changes of the load value. In this way, the frequency is
continually updated. After 60 seconds of inactivity the optimised frequencies are discarded because the motor may
have cooled down, in which case the dynamic frequency search will be performed again once motion is restarted.
In certain applications, it may be inconvenient to wait for the search to be performed each time the motor is stopped
for a time. In this case, the user should store the last frequency used before stopping the slider, and then reload
the frequencies before restarting the motion.
Rev. G, April 2018
Chapter 4: Operation
Page 11