3 reversal error compensation – Rockwell Automation 8520-ARM2 9/Series CNC AMP Reference Manual Documentation Set User Manual
Page 175

Servo Parameters
Chapter 7
7-29
Axis
Parameter
Number
Axis
Parameter
Number
(1)
[1590]
(7)
[7590]
(2)
[2590]
(8)
[8590]
(3)
[3590]
(9)
[9590]
(4)
[4590]
(10)
[10590]
(5)
[5590]
(11)
[11590]
(6)
[6590]
(12)
[12590]
Range
0.000 to 254.000 mm
0.000 to 10.000 in.
Notes
This parameter must be set independently for each servo.
Function
When an axis is commanded to reverse direction, mechanical play in the
machine (through the gearing, ballscrew, etc.) may result in a small amount
of motor motion without axis motion. As a result, the feedback device
may indicate movement even though the axis has not moved.
The control uses the value entered for the Reversal Error Compensation
parameter to compensate for this motion. The value entered is added to the
beginning of the commanded axis motion.
Important: Verify that the reversal error value entered here is not greater
than the actual mechanical reversal error. If too large a value is entered, it
interferes with proper axis motion.
The sign included with this parameter value is used only to establish the
initial reversal error direction as described below.
If the value is
entered as:
then it is added to the first
move in this direction:
and, from that time on:
negative
positive
any time the axis reverses direction, the
Reversal Error Compensation distance is added
to the move distance
positive
negative
7.2.3
Reversal Error
Compensation