Rockwell Automation 1771-QC , D17716.5.25 SER/B SERVO POS - Manual (Page 103)

Formatting and Interpreting Data Blocks
Chapter 7
7Ć21
Important: The address pointer value you enter in each of these words
must be a BCD value other than 000.
For each axis, include only the address of the first moveset block in the
parameter block. Include address pointers to subsequent movesets in the
blocks that precede them. If you program an escape move, you must enter
its address in the parameter block moveset address pointer word. You
must do this because the escape move must be the first moveset
transferred to the 1771-M3 controller, even though it is not the first
moveset normally executed.
Feedback Resolution
Feedback resolution is the smallest unit of axis motion that can be
distinguished by the servo positioning assembly. That is, it is the distance
the axis moves per feedback increment.
Enter the value of feedback resolution in the feedback resolution word of
the parameter block (Figure 7.11). As described in chapter 3, feedback
resolution is determined by the number of encoder lines, the feedback
multiplier, and leadscrew pitch:
Feedback Resolution = Axis Displacement per Encoder Rev.
(Encoder Lines) (Feedback Multiplier)
If the system has no gearing, the axis displacement per revolution is the
same as the leadscrew pitch or lead.
Figure 7.11
Feedback Resolution Word
17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00
Feedback Resolution
Word 7 (Axis 1)
11033
Word 26 (Axis 2)
Word 45 (Axis 3)
0 = inches x 10
1 = millimeters x 10 -5
-6
Feedback resolution, BCD format
(0010 minimum)