Delta MMC120 - Manual (Page 74)

74
Parameter Errors
Target position moved outside limits
This parameter error indicates that the axis was about to move its Target Position outside
the extend or retract limit. The target position is truncated to the limit when this error
occurs. Commands that have a requested position outside the limits are caught
immediately by the “ Attempt to go beyond extend limit ” and “ Attempt to go beyond the
retract limit ” parameter errors.
Therefore, the only way this error can occur is by lowering the deceleration rate in the
middle of a move enough so that the axis overshoots the commanded position and limit.
We could catch this error when the command is issued but do not because some
applications have an axis decelerate slowly for a period of time, but then issue another
command to stop it within the limits. These applications would be impossible if we
didn’t allow this deceleration even though, if uninterrupted, it would bring the axis
outside the limit.
NOTE: This error will not occur when the Actual Position goes outside the limits.
That is, you will be able to control position at either limit even though the
Actual Position may go outside the limits temporarily.
FLASH contained no data on startup
This parameter error will appear on either the first or second axis on startup whenever
there is a problem loading the parameters or event steps from FLASH memory . If this
parameter occurs on axis 1, then profiles and parameters could not be loaded. If this
parameter occurs on axis 2, then event steps could not be loaded. Default will be used.
To store parameters in the FLASH, load the motion controller with all desired
configuration parameters, and issue a Update FLASH command. You must wait for the
ACK to toggle—indicating that the FLASH write is complete—before powering off the
module. If this parameter error appears, one of the following has occurred:
• The module is newly shipped. New modules have no data stored in the FLASH.
• The module was powered down while updating the FLASH. This results in an
invalid checksum being found for the data, so the FLASH is not usable on next
power-up.
• The FLASH itself has a problem with it. If you find that the FLASH consistently
does not store data, although the module is not being powered down while the
FLASH is being written to, contact the manufacturer for details on having the FLASH
replaced.