
Rockwell Automation Publication 2198-UM002E-EN-P - February 2018
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Kinetix 5700 Safe Torque-off Function
Chapter 9
Understand STO Bypass When Using Motion Direct Commands
If a Safety-only connection between the GuardLogix safety controller and the
Kinetix 5700 servo drive was established at least once after the drive was
received from the factory, the drive does not allow motion while the safety
controller is in Program mode by default.
This is because the safety task is not executed while the GuardLogix safety
controller is in Program mode. This applies to applications running in a single-
safety controller (with Motion and Safety connections). When an integrated
safety drive has a Motion connection to a standard controller and a separate
Safety connection to a safety controller, the standard controller can transition
to Program mode while the safety controller stays in Run mode and continues
to execute the safety task.
However, Kinetix 5700 drive systems are designed with a bypass feature for the
STO function in single-safety controller configurations. You can use the MDC
feature to allow motion while following all the necessary and prescribed steps
per your machine’s safety operating procedures.
ATTENTION:
To avoid personal injury or damage to equipment, follow these
rules regarding Run mode and Program mode.
• Only authorized, trained personnel with knowledge of safe machine
operation should be allowed to use Motion Direct Commands
• Additional supervisory methods, like removing the controller key switch,
should be used to maintain the safety integrity of the system after returning
the safety controller to RUN mode
ATTENTION:
Consider the consequences of allowing motion through the use
of MDC when the controller is in Program mode. You must acknowledge
warning messages in the Logix Designer application that warn of the drive
bypassing the STO function and unintended motion can occur. The integrated
safety drive does not respond to requests of the STO function if MDC mode is
entered.
It is your responsibility to maintain machine safety integrity while executing
motion direct commands. One alternative is to provide ladder logic for
Machine Maintenance mode that leaves the controller in Run mode with
safety functions executing.