Rockwell Automation Publication PFLEX-UM003D-EN-P - June 2021
21
Description of Operation
Connection Examples
Example 1 - Safe Torque Off Connection with Coast-to-Stop Action, Dual Channel
Figure 10 - Stop Category 0 – Coast
Circuit Status
Circuit shown with guard door closed and system ready for normal drive operation.
Operating Principle
This is a dual channel system with monitoring of the Safe Torque Off circuit and drive.
Opening the guard door will switch the input circuits (S13…S14 and S21…S22) to the
Minotaur™ monitoring safety relay unit. The output circuits (13…14 and 23…24) will
cause the Safe Torque Off option and drive Enable circuit to trip and the motor will
coast to stop. To restart the drive, the Minotaur safety relay must first be reset
followed by a valid start command to the drive.
Fault Detection
A single fault detected on the Minotaur safety input circuits will result in the lock-out
of the system at the next operation and will not cause loss of the safety function.
If the Safe Torque Off option sticks On, the motor will stop on command due to the
enable input. The system cannot be reset when this fault condition exists.
Stop
Start
A1 S21 S13
31 13 23 X1
A2
+24V DC
Common
+24V DC
S22 S14
32 14 24 X2
Minotaur
MSR9T
GuardMaster
Trojan
Gate
+24V DC
PowerFlex
AC Drive
Stop
Start
AC Line
Input Power
Common
Enable
*
M
1
2
3
4
Safe Off Option
IMPORTANT
The drive Enable digital input is a solid
state circuit. The safety outputs on safety
module must not be configured for
Pulsed/Safety Pulse Test.
