ABB RELION REB670, Applications Manual

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Section 8 Voltage protection
8.1 Two step undervoltage protection UV2PTUV (27)
IP14544-1 v3
8.1.1 Identification
M16876-1 v7
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Two step undervoltage protection UV2PTUV
3U<
SYMBOL-R-2U-GREATER-THAN V2 EN-US
27
8.1.2 Setting guidelines
M13851-3 v9
All the voltage conditions in the system where UV2PTUV (27) performs its functions
should be considered. The same also applies to the associated equipment, its voltage
and time characteristic.
There is a very wide application area where general undervoltage functions are used.
All voltage-related settings are made as a percentage of the global base value
VBase ,
which normally is set to the primary rated voltage level (phase-to-phase) of the power
system or the high voltage equipment under consideration.
The trip time setting for UV2PTUV (27) is normally not critical, since there must be
enough time available for the main protection to clear short circuits and ground faults.
Some applications and related setting guidelines for the voltage level are described in
the following sections.
8.1.2.1 Equipment protection, such as for motors and generators
M13851-50 v3
The setting must be below the lowest occurring "normal" voltage and above the lowest
acceptable voltage for the equipment.
1MRK 505 370-UUS A
Section 8
Voltage protection
Busbar protection REB670 2.2 ANSI 243
Application manual