ABB Relion REG670, Руководство оператора

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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 earth-fault protection function
TNC connector Threaded Neill Concelman, A threaded constant impedance
version of a BNC connector
TPZ, TPY, TPX,
TPS Current transformer class according to IEC
Underreach A term used to describe how the relay behaves during a fault
condition. For example a distance relay is under-reaching
when the impedance presented to it is greater than the
apparent impedance to the fault applied to the balance point,
i.e. the set reach. The relay does not “see” the fault but
perhaps it should have seen it. See also Overreach.
U/I-PISA Process interface components that deliver measured voltage
and current values
UTC Coordinated universal time. A coordinated time scale,
maintained by the Bureau International des Poids et Mesures
(BIPM), which forms the basis of a coordinated
dissemination of standard frequencies and time signals. UTC
is derived from International Atomic Time (TAI) by the
addition of a whole number of "leap seconds" to synchronize
it with Universal Time 1 (UT1), thus allowing for the
eccentricity of the Earth"s orbit, the rotational axis tilt (23.5
degrees), but still showing the Earth"s irregular rotation, on
which UT1 is based. The Coordinated Universal Time is
expressed using a 24-hour clock and uses the Gregorian
calendar. It is used for aeroplane and ship navigation, where
it also sometimes known by the military name, "Zulu time".
"Zulu" in the phonetic alphabet stands for "Z" which stands
for longitude zero.
UV Undervoltage
WEI Weak end infeed logic
VT Voltage transformer
X.21 A digital signalling interface primarily used for telecom
equipment
3I
O
Three times zero-sequence current. Often referred to as the
residual or the earth-fault current
1MRK 502 014-UEN C
Section 15
Glossary
99
Operator's manual