
Rockwell Automation Publication 1734-UM013C-EN-P - August 2010
29
Safety Functions
Chapter
2
Dual-channel Setting
When the data of both channels is in the on state, and neither channel has a fault,
the outputs are turned on. The status is normal. If a fault is detected on one
channel, the safety output data and individual safety output status turn off for
both channels.
Figure 13 - Dual-channel Setting (not to scale)
Safety Output Fault Recovery
If a fault is detected, the safety outputs are switched off and remain in the off
state. Follow this procedure to activate the safety output data again.
1.
Remove the cause of the error.
2.
Command the safety output (or safety outputs) into the safety state.
3.
Allow the output-error latch time to elapse.
After these steps are completed, the I/O indicator (red) turns off.
The output data can now be controlled.
IMPORTANT
Stuck high faults require a module power reset to clear
the error.
ON
OFF
OUT0
Safety Output
Status 0, 1
OUT0
OUT1
OUT1
Safety Output
Status 0, 1
Fault Detection
Error
Detected
ON
OFF
ON
OFF
ON
OFF
ON
OFF
ON
OFF
Normal Operation
Safety
I/O
Network
Data Sent
to the
Controller
Safety
I/O
Network
Data Sent
to the
Controller