Rockwell Automation 1756-IH16ISOE ControlLogix Sequence of Events Module - Manual (Page 152)

Publication 1756-UM528A-EN-P - April 2004
Glossary 4
Removable terminal block (RTB)
Field wiring connector for Sequence of Events modules
Requested packet interval (RPI)
The maximum amount of time between broadcasts of I/O data
Run mode
In this mode, the following events occur:
• Controller program is executing
• Inputs are actively producing data
Service
A system feature that is performed on user demand, such as fuse reset
or diagnostic latch reset
System side
Backplane side of the interface to the Sequence of Events module
Tag
A named area of the controller’s memory where data is stored
Time master
Device, either ControlLogix controller or 1756-SYNCH module, that
sets the CST time for a ControlLogix chassis and/or SynchLink system.
Timestamping
ControlLogix process that stamps a change in input data with a
relative time reference of when that change occurred
Universal Coordinated Time (UCT)
World standard time format maintained by atomic clocks operated by
government organizations around the world. The 1756HP-GPS
module reports UTC as a 64-bit unsigned long integer representing the
number of elapsed microseconds since 1 January 1972.
Wall clock time (WCT)
Gregorian time format. In this format, time is represented in year,
month, day, hour, minute, second and microsecond.