GE Mark VIe System Manual page 197

Sequence of Events (SOE) A high-speed record of contact transitions taken during a plant upset to allow detailed
analysis of the event.
Server A computer that gathers data over the Ethernet from plant devices, and makes the data available to computer-based
operator interfaces known as viewers.
Simplex Operation that requires only one set of control and I/O, and generally uses only one channel. The entire Mark VIe
control system can operate in simplex mode.
Simulation Running a system without all of the configured I/O devices by modeling the behavior of the machine and the
devices in software.
Software Implemented Fault Tolerance (SIFT) A technique for voting the three incoming I/O data sets to find and
inhibit errors. Note that control also uses output hardware voting.
TCP/IP Communication protocols developed to inter-network dissimilar systems. It is a de facto UNIX standard, but is
supported on almost all systems. TCP controls data transfer and IP provides the routing for functions, such as file transfer and
e-mail.
ToolboxST A Windows-based software package used to configure the control systems, exciters, and drives.
Trend A time-based plot to show the history of values, similar to a recorder, available with the ControlST Historian and the
ToolboxST application.
Triple Module Redundancy (TMR) An operation that uses three identical sets of control and I/O (channels R, S, and T)
and votes the results.
Unit Data Highway (UDH) Connects the controllers, static starter control system, excitation control system, PLCs, and
other GE provided equipment to the HMI Servers.
GEH-6721_Vol_I_BP Glossary of Terms 197
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