Rockwell Automation 1771-QB Linear Pos. - Manual (Page 97)

Formatting Module Data (WRITES)
Chapter 7
7Ć18
Proportional Gain (words 17 and 46)
The module uses the proportional gain factor K
P
at axis speeds below the gain
break speed.
Figure 7.23
Proportional Gain Word
50023
Proportional gain,
BCD or binary
0.9999 ips/mil or 0.9999 mmps/mil max
(1 mil = 0.001 inch or 0.001 millimeter.)
15 14 13 12 11 10 09 08 07 06 05 04 03 02 01 00
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The proportional gain is defined as the ratio of the axis speed divided by the
positioning error (or following error):
proportional gain = axis speed/positioning error
Proportional gain effects axis response to positioning commands. Figure 7.24
shows how different gain values affect system responsiveness.
Figure 7.24
Following Error vs Speed for Various Gains
Analog Output
(Axis Speed)
Following
Error
50068
High Gain
High Gain,
Low Following Error
Low Gain
Low Gain,
High Following Error