Allen-Bradley controllogix 1756-L63, User Manual

Page: 400 / 435

Publication 1756-UM001E-EN-P - August 2002
24-20 Program Motion Control
In your ladder logic program, you can modify motion configuration
parameters using the SSV instruction. For example, you can change
position loop gain, velocity loop gain, and current limits within your
program.
For more information on the SSV instruction, see the following
publications:
•
Logix5000 Controllers General Instructions Reference Manual ,
publication 1756-RM003
•
ControlLogix Motion Module Setup and Configuration Manual ,
publication 1756-UM006
Handle Motion Faults
Two types of motion faults exist.
You can configure a fault as either minor or major by using the Axis
Wizard-Group window.
Understanding errors
Executing a motion instruction within an application program can
generate errors. The MOTION_INSTRUCTION tag has a field that
contains the error code. For more information about error codes for
individual instructions, see the
Logix5000 Controllers Motion
Instruction Set Reference Manual , publication 1756-RM007.
Understanding minor/major faults
Several faults can occur that are not caused by motion instructions.
For example, a loss of encoder feedback or an actual position
exceeding an overtravel limit will cause faults. The motion faults are
considered type 2 faults with error codes from 1 to 32. See
Logix5000
Controllers Common Procedures , publication 1756-PM001.
Type Description Example
Errors
•
Do not impact controller operation
•
Should be correct to optimize
execution time and ensure
program accuracy
A Motion Axis Move
(MAM) instruction
with a parameter out
of range
Minor/Major
•
Caused by a problem with the
servo loop
•
Can shutdown the controller if you
do not correct the fault condition
The application
exceeded the
PositionErrorTolerance
value.