Rockwell Automation 2198-Hxxx Kinetix 5500 Servo Drives User Manual - Manual (Page 181)

Rockwell Automation Publication 2198-UM001D-EN-P - May 2014 181
Kinetix 5500 Safe Torque-off - Integrated Safety Chapter 10
Motion Direct Commands in
Motion Control Systems You can use the Motion Direct Command (MDC) feature to initiate motion
while the controller is in Program mode, independent of application code that is
executed in Run mode. These commands let you do a variety of functions, for
example, move an axis, jog an axis, or home an axis.
A typical use might involve a machine integrator testing different parts of the
motion system while the machine is being commissioned or a maintenance
engineer, under certain restricted scenarios in accordance with safe machine
operating procedures, wanting to move an axis (like a conveyor) to clear a jam
before resuming normal operation.
Understanding STO Bypass When Using Motion Direct Commands
If a Safety-only connection between the GuardLogix safety controller and the
2198-H
xxx-ERS2 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 dual-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, 2198-H
xxx-ERS2 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 machine 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 the request of STO function if MDC mode is entered.
ATTENTION: 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.