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TB178 Rev1 Servo Drive Shutdown Messages During EStop
Problem Description
It is possible to get a 436 "Servo drive Shutdown" message when the estop button is depressed on systems
with SD1 drives on the 4th and 5th axes This problem does not affect the control and can be recovered by
cycling the estop button multiple times
Problem Background
The problem is caused by the individual SD1 drives issuing an undervoltage alarm to the CPU in series This
series confuses the CPU and allows the Servo Drive Fault Bit 64 to be latched in the PLC table Once latched
the Servo Drive Fault bit can only be cleared by cycling the estop button
Resolution
The "Servo Drive Shutdown" message appearing during an estop state can be cleared by pressing and
releasing the estop in rapid succession multiple times Software releases after version 1 26 will not exhibit this
problem
Document History
Rev1 Created on 2005 09 09