Rockwell Automation GMLC Reference Manual - Manual (Page 107)

Publication GMLC-5.2 - November 1999
70 Configuring Axis Use
Filter Lag Limit
The Filter Lag Limit parameter sets the value for the maximum allowable
filter induced lag which the controller cannot exceed. Enter a value
representing the maximum permissible filter-induced lag in position units
(as determined at the Units Tab) between the filtered output and actual
position. Commander lets you enter a value between 0 and 1000 position
units.Use the following formula to determine the filter induced steady
state lag for a given constant velocity and filter bandwidth:
Lag = (velocity x (BW x servo period + 1)/BW) – (velocity x servo period)
where:
• velocity = units per second
• servo period = seconds
• bandwidth (BW) = Hz.
Note: When filter-induced lag exceeds the input value, the controller
turns the encoder filter OFF. When filter-induced lag falls below
the input value, the controller turns the encoder filter back ON.
Defining Position
The Defining Position page is used for entering settings that determine a
physical axis motion and positioning.