Rockwell Automation 1734-IE4S POINT Guard I/O Safety Modules User Manual - Manual (Page 30)

30 Rockwell Automation Publication 1734-UM013J-EN-P - July 2014
Chapter 2 Safety Inputs, Safety Outputs, and Safety Data
Safety Input Fault Recovery
If an error is detected, the safety input data remains in the OFF state. Follow this
procedure to activate the safety input data again.
1. Remove the cause of the error.
2. Place the safety input (or safety inputs) into the safe state.
3. Allow the input-error latch time to elapse.
After these steps are completed, the I/O indicator (red) turns off.
The input data is now active.
Input Delays
On-delay—An input signal is treated as Logic 0 during the on-delay time
(0…126 ms, in increments of 6 ms) after the input contact’s rising edge. The
input turns on only if the input contact remains on after the on-delay time has
elapsed. This helps prevent rapid changes of the input data due to
contact bounce.
Figure 10 - On-delay
Off-delay—An input signal is treated as Logic 1 during the off-delay time
(0…126 ms, in increments of 6 ms) after the input contact’s falling edge.
The input turns off only if the input contact remains off after the off delay time
has elapsed. This helps prevent rapid changes of the input data due to contact
bounce.
Figure 11 - Off-delay
44094 On-delay
ON
OFF
ON
OFF
Input Signal
Safety Input
Network Data
44095
Safety Input
Network Data
Off-delay
Input Signal
ON
OFF
ON
OFF