Filter wheels
Sometimes filter wheel parameters need to be adjusted. Typically this happens when the weight of the filters is too great for the standard parameters and the wheel must be slowed down, or when the application requires all possible speed and the wheel must be sped up. Of course, parameters differ for 12/10-position wheels with standard or long motors and for 22/18 position wheels. The download page contains typical parameters for these situations, which have descriptive names. In ScopeTool these parameter files can be loaded from F (or B)/Advanced/Read Par File, or the parameter file can be edited in Notepad.
The following parameters describe filter wheels F and B. They are stored in files ST_PARW1.TXT (for wheel F) and ST_PARW2.TXT (for wheel B). The names of parameters indicate in the second character whether they are for wheel F (1) or for wheel B (2).
| Parameter Name | Typical value for EZHR17EN controller | Explanation an typical range of values |
|
W1CONTR / W2CONTR |
1 / 2 |
Name of F / B wheel controller. |
|
W1HOLDCURRENT / W2HOLDCURRENT |
10 |
Hold current in % of max (2A). |
|
W1RUNCURRENT / W2RUNCURRENT |
70 |
Run current in % of max (2A). |
|
W1SLEWVELOCITY / W2SLEWVELOCITY |
8000 |
Slew velocity in microsteps per second. Increase for faster moves, Decrease for more torque. [5000 to 40000]. |
|
W1INITVELOCITY / W2INITVELOCITY |
1000 |
Initial velocity in microsteps per second. Increase for faster moves, Decrease for heavier loads. [500 to 2000] |
|
W1ACCELERATION / W2ACCELERATION |
10 |
Acceleration in microsteps per second^2. Increase for faster moves, Decrease for heavier loads. [10 to 20] |
|
W1OFFSETHOME / W2OFFSETHOME |
-2 |
Microsteps from physical home to filter #1. [-6 to 4] |
|
W1FILTPOSITIONS / W2FILTPOSITIONS |
12 |
Number of filter positions in the wheel [12, 10, 22, 18]. |
Focus Drive
Focus drive parameters may need adjustment depending on the presence of focus limits or if the tension on the fine focus is unusually high. Parameters can be changed from within the application, or edited in Notepad.
| Parameter Name | Typical value for EZHR17EN controller | Explanation an typical range of values |
|
ZCONTR |
2 |
Name of focus controller. |
|
ZSTROKEPERROT |
0.1 |
Z travel per one turn of the fine focus shaft in mm. |
|
ZMOTORSTEPS |
400 |
Number of full motor steps in one revolution. |
|
ZSTEPDIVIDE |
8 |
Microstepping divide factor. One microstep = 1 / 2^stepdivide of full step. |
|
ZHOLDCURRENT |
5 |
Hold current in % of max (2A). This parameter can be set to 0 for smoother manual operation. |
|
ZRUNCURRENT |
25 |
Run current in % of max (2A). |
|
ZSLEWVELOCITY |
40000 |
Slew velocity in microsteps per second. Increase for faster moves, Decrease for more torque. |
|
ZINITVELOCITY |
1000 |
Initial velocity in microsteps per second. Increase for faster moves, Decrease for heavier loads. |
|
ZACCELERATION |
10 |
Acceleration in microsteps per second^2. Increase for faster moves, Decrease for heavier loads. |
|
ZDECELERATION |
10 |
Deceleration for EZHR17EN is always the same as acceleration. |
|
ZBACKLASH |
microscope-dependent |
Added travel when direction is reversed. |
|
ZJUMPSIZE |
1 |
Travel when fine button is pressed in the interface in microns |
|
ZCOARSEFACTOR |
10 |
Factor by which coarse step in the interface is larger than fine step. |
|
ZJOYMAXSPEED |
20000 |
Maximal speed when moved by joystick. |
|
ZHOMESPEED |
10000 |
Homing speed. If Focus limit is installed. |
|
ZPOWERUPORIGIN |
0 |
Position count assigned at first initialization after power up. |
|
ZLIMPOLARITY |
0 |
0 for normally open, 1 for normally closed switches. If Focus limit is installed. |
|
ZENABLELIMITS |
0 |
1 - If Focus limit is installed. |