Rockwell Automation Publication 1756-RM093J-EN-P - April 2018
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Appendix
C
Reaction Times
System Reaction Time
To determine the system reaction time of any control chain, you must add up the
reaction times of all of components of the safety chain.
System Reaction Time = Sensor Reaction Time + Logix System Reaction Time
+ Actuator Reaction Time
Figure 19 - System Reaction Time
Logix System Reaction Time
The following sections provide information on calculating the Logix System
Reaction Time for a simple input-logic-output chain and for a more complex
application using produced/consumed safety tags in the logic chain.
Topic
Page
System Reaction Time
Sensor Reaction
Time
Input Reaction
Time
Safety Task
Reaction Time
Output Reaction
Time
Actuator
Reaction Time
Logix System Reaction Time
Input Module
Delay
Input Connection
Reaction Time Limit
Safety Task Period
+
Safety Task Watchdog
Output Connection
Reaction Time Limit
Output Module
Delay
