Allen-Bradley DriveGuard PowerFlex 700S User Manual page 18

16 Description of Operation
Example 1
Safe-Off Connection with Coast-to-Stop Action, Dual Channel
Figure 2
+24V DC
GuardMaster
Gate
Trojan
+24V DC
Common
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-off circuit and drive. Opening the guard door will switch the
input circuits (S13-S14 & S21-S22) to the Minotaur monitoring safety
relay unit. The output circuits (13-14 & 23-24) will cause the Safe-Off
option and drive Enable circuit to go immediately to a safe state (off) and
the motor will coast to stop. To restart the drive, the Minotaur safety
relay inputs (S13-S14, S21-S22) must first be ready for normal drive
operation 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 to a safe state (off) at the
next operation and will not cause loss of the safety function.
If the Safe-Off option sticks ON, the motor will stop on command due to
the enable input. The system cannot be reset and thereby reveals the fault
condition to the operator.
Application Considerations – When the hazard analysis for the overall
machine determines the need for external mechanical brakes or other
stopping means, the external means shall be activated after the removal
of power for Stop Category 0.
Stop Category 0 – Coast
A1 S21 S13 31 13 23 X1
Minotaur
MSR9T
A2 S22 S14 32 14 24 X2
PowerFlex 700S
AC Drive
+24V DC
Stop
Stop
Start
Start
Start/Stop Common
24V DC Common
Gate Control
Power Supply
Safe Off Option
3
4
1
2
Gate Control
Circuit
Common
Enable
AC Line
Input Power
M