ABB RELION 650 SERIES, Technical Manual

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RTU Remote terminal unit
SA Substation Automation
SBO Select-before-operate
SC Switch or push button to close
SCL Short circuit location
SCS Station control system
SCADA Supervision, control and data acquisition
SCT System configuration tool according to standard IEC
61850
SDU Service data unit
SFP Small form-factor pluggable (abbreviation)
Optical Ethernet port (explanation)
SLM Serial communication module.
SMA connector Subminiature version A, A threaded connector with
constant impedance.
SMT Signal matrix tool within PCM600
SMS Station monitoring system
SNTP Simple network time protocol – is used to synchronize
computer clocks on local area networks. This reduces the
requirement to have accurate hardware clocks in every
embedded system in a network. Each embedded node can
instead synchronize with a remote clock, providing the
required accuracy.
SOF Status of fault
SPA Strömberg Protection Acquisition (SPA), a serial master/
slave protocol for point-to-point and ring communication.
SRY Switch for CB ready condition
ST Switch or push button to trip
Starpoint Neutral point of transformer or generator
SVC Static VAr compensation
TC Trip coil
TCS Trip circuit supervision
TCP Transmission control protocol. The most common
transport layer protocol used on Ethernet and the Internet.
TCP/IP Transmission control protocol over Internet Protocol. The
de facto standard Ethernet protocols incorporated into
4.2BSD Unix. TCP/IP was developed by DARPA for
Internet working and encompasses both network layer and
1MRK 506 382-UEN A
Section 24
Glossary
Line distance protection REL650 2.2 IEC 931
Technical manual