Rockwell Automation 8520 9/Series CNC Integration Maintenance Manual Documentation Set - Manual (Page 748)

Section 15A
Troubleshooting The Control
15A-38
Beneath the servo name are several rows of servo data. This data is
displayed:
FOLLOWING ERROR This indicates the following error in inches, millimeters or degrees.
DISTANCE TO MARKER This indicates the distance from the current axis position to the
nearest encoder marker in inches or millimeters. The display rolls
over at 1/2 the distance between markers. At this rollover point, the
display switches sign depending on the direction of rotation. At the
actual marker, the display reads zero.
HM DIST This value is the distance to the marker calculated when the axis
stopped after the home switch went false, during the last home
operation. Value is in this axis’s programming units. If the axis does
not requrie homing , or if a “switchless”home was executed on this
axis, a value of 0.0 will be displayed. Only visable for servo AXES.
HM TOL This is a static display of the value set in AMP to detect a home
tolerence error. A value in the “HM DIST” larger than this limit
indicates that an error has occured.
COMMANDED
TORQUE
This is the torque output being commanded to the motor for the axis
being monitored. It is expressed as a percentage of rated torque (0 to
300%) defined in AMP as the torque limit for that axis. The sign
indicates the direction of commanded torque. This value is also
available in PAL. Refer to $TORQ.
SPINDLE DAC COMMAND This is an integer number reflecting the digital output to the DAC. The
same value is displayed for every axis (except the split axis slave
servo). Only visable for “spindls”. This value is calculated as follows:
[Voltage at Max for Gear n ][ Commanded RPM ] x 4096 _____________________________________________________________
[ Maximum Spindle Speed - Gear n ] x 10
[Voltage at Max for Gear n ] and
[ Maximum Spindle Speed - Gear n ] are AMP parameters.
SKEW Skew data is only displayed on the axis screen of a split axis slave
servo. The value shown here as skew indicates the difference in
following error between the split axis master servo and the split axis
slave servo.
The status of the following error and the distance from marker/null are
displayed in the lower right corner of the screen. It is displayed as one of
the following:
IN-POSITION The absolute value of the following error is less than the value
of the INPOSITION BAND parameter.
< FEEDRATE SUPPRESSION The absolute value of the following error is greater than the
value of the INPOSITION BAND parameter, but is less than the
value of the FEEDRATE SUPPRESSION POINT parameter.
> FEEDRATE SUPPRESSION The absolute value of the following error is greater than the
value of the FEEDRATE SUPPRESSION POINT parameter.
EXCESS ERROR The absolute value of the following error is greater than the
value of the EXCESS ERROR parameter.
The status of the distance from marker/null is displayed as either: