ABB Relion 670 Series RES670, Technical Manual

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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/Wye 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 transport layer
protocols. While TCP and IP specify two protocols at specific
protocol layers, TCP/IP is often used to refer to the entire US
Department of Defense protocol suite based upon these,
including Telnet, FTP, UDP and RDP.
TEF Time delayed gound-fault protection function
TLS Transport Layer Security
TM Transmit (disturbance data)
TNC connector Threaded Neill-Concelman, a threaded constant impedance
version of a BNC connector
TP Trip (recorded fault)
TPZ, TPY, TPX, TPS Current transformer class according to IEC
TRM Transformer Module. This module transforms currents and
voltages taken from the process into levels suitable for further
signal processing.
TYP Type identification
UMT User management tool
Underreach A term used to describe how the relay behaves during a fault
condition. For example, a distance relay is underreaching when
the impedance presented to it is greater than the apparent
impedance to the fault applied to the balance point, that is, the
Section 25
1MRK 511 365-UUS A
Glossary
878 Phasor measurement unit RES670 2.1 ANSI
Technical manual