
B-63945EN/02 9.DIGITAL SERVO
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CAUTION
In addition to the parameters listed above, there are
parameters to be set using the detection unit.
This change eliminates an error between the required number of
position pulses per motor revolution and the reference counter.
Required number of position pulses per motor revolution =
20000
Reference counter = 20000
(b) For the closed loop
Reference counter = Z phase (reference position) interval/detection unit or
the same number divided by an integer
If the reference counter does not assume an integer, see the
example of semi-closed loop.
NOTE
If the rotation ratio between the separate detector
and table is not an integer when a rotation axis is
used, a reference counter capacity needs to be set
so that the point where reference counter = 0 (grid
point) always appears at the same position relative
to the table.
Example of setting)
Example 1)
When Z phase interval = 50 mm and detection unit = 1 µm
Reference counter = 50,000/1 = 50,000
Example 2)
When detection unit = 0.001° with a rotation axis
Reference counter = 360/0.001 = 360,000
Example 3)
When there is only one Z phase as in the case of a linear scale
Set a simple number such as 10000 and 50000 for the reference
counter.
6. Turn off the power then back on.