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Rockwell Automation Publication 1756-RM093J-EN-P - April 2018
Appendix C
Reaction Times
Simple Input-logic-output Chain
Figure 20 - Logix System Worst-case Reaction Time for Simple Input to Logic to Output
The Logix System Reaction Time for any simple input to logic to output chain
consists of these five components:
1.
Safety input module reaction time plus input delay time
2.
Safety Input Connection Reaction Time Limit
(Read from the Module Properties dialog box in RSLogix 5000 software,
this value is a multiple of the safety input module connection RPI.)
3.
Safety Task Period plus Safety Task Watchdog time
4.
Safety Output Connection Reaction Time Limit
(Read from the Module Properties dialog box in RSLogix 5000 software,
this value is a multiple of the safety task period.)
5.
Safety output module reaction time
To aid you in determining the reaction time of your particular control loop, a
Microsoft Excel spreadsheet is available in the Tools folder of the RSLogix 5000
software CD.
1. Safety Input
Module Delay
5. Safety Output
Module Delay
2. Safety Input Connection
Reaction Time Limit
4. Safety Output Connection
Reaction Time Limit
CIP Safety Network
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3. Safety Task
Safety Task Watchdog
