Rockwell Automation Publication 1756-RM012B-EN-P - April 2018 107
Glossary
symbolic addressing A method of addressing that provides an ASCII interpretation of the tag name.
system reaction time The worst case time from a safety-related event as input to the system or as a
fault within the system, until the time that the system is in the safe state. System
reaction time includes sensor and actuator Reaction Times, Input and Output
Reaction Times (including network connection delays), and the Controller
Reaction Time.
systematic capability (SC) A confidence that the systematic safety integrity meets the requirements of the
specified safety integrity level (SIL). (from IEC 61508-4)
task A scheduling mechanism for executing a program. A task provides scheduling
and priority information for a set of one or more programs that execute based
on a certain criteria. Once a task is triggered (activated), all programs assigned
(scheduled) to the task execute in the order in which they are displayed in the
controller organizer.
test edits Once online edits have been accepted, there are two versions of user logic
residing in controller memory. The Test Edits command in the Studio 5000
Logix Designer application causes the controller to execute the new, edited
version of user logic. The original, unedited version of user logic is still in
controller memory, but is not executed. See untest edits
.
timeout multiplier This value determines the number of messages that can be lost before declaring
a connection error. See also network delay multiplier
.
undetected failure A failure that is undetected by diagnostic tests, proof tests, operator
intervention, or through normal operation.
untest edits Once online edits have been accepted, there are two versions of user logic
residing in controller memory. The Untest Edits command in the Studio 5000
Logix Designer application causes the controller to execute the original,
unedited version of user logic. The new, edited version of user logic is still in
controller memory, but is not executed. See test edits
.
valid connection Safety connection is open and active, with no errors.
To Next Page
Loading...
Need help?
General
