Allen-Bradley PowerFlex 527, Руководство пользователя

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Rockwell Automation Publication 520-UM002B-EN-E - December 2017 115
Network Control of Safe Torque-Off Chapter 6
Understanding STO Bypass When Using Motion Direct Commands
If a Safety-only connection between the GuardLogix safety controller and the
PowerFlex 527 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, PowerFlex 527 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.
Logix Designer Application Warning Messages
When the controller is in Run mode, executing safety functions, the
PowerFlex 527 drive follows the commands that it receives from the safety
controller. The controller will report Safety state = Running and Axis state =
Stopped/Running, as shown in
Safety State Indications When Controller is in
Run Mode (safety task executing) on page 116 .
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.
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.