ABB Relion REG670, Technical Manual

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10.3.8 Technical data
Table 319: SAPFRC Technical data
Function Range or value Accuracy
Operate value, start function (-10.00-10.00) Hz/s ±10.0 mHz/s
Operate value, restore
enable frequency
(45.00-65.00) Hz ±2.0 mHz
Definite restore time delay (0.000-60.000) s ±0.2% or ±100 ms whichever is
greater
Definite time delay for
frequency gradient trip
(0.200-60.000) s ±0.2% or ±120 ms whichever is
greater
Definite reset time delay (0.000-60.000) s ±0.2% or ±250 ms whichever is
greater
10.4 Frequency time accumulation protection function
FTAQFVR
10.4.1 Identification
Function description IEC 61850
identification
IEC 60617
identification
ANSI/
IEEEidentification
Frequency time accumulation protection FTAQFVR f<> 81A
10.4.2 Functionality
Frequency time accumulation protection FTAQFVR is based on measured system
frequency and time counters. FTAQFVR for generator protection provides the
START output for a particular settable frequency limit, when the system frequency
falls in that settable frequency band limit and positive sequence voltage within
settable voltage band limit. The START signal triggers the individual event timer,
which is the continuous time spent within the given frequency band, and the
accumulation timer, which is the cumulative time spent within the given frequency
band. Once the timers reach their limit, an alarm or trip signal is activated to protect
the turbine against the abnormal frequency operation. This function is blocked during
generator start-up or shut down conditions by monitoring the circuit breaker position
and current threshold value. The function is also blocked when the system positive
sequence voltage magnitude deviates from the given voltage band limit which can be
enabled by
EnaVoltCheck setting.
It is possible to create functionality with more than one frequency band limit by using
multiple instances of the function. This can be achieved by a proper configuration
based on the turbine manufacturer specification.
1MRK502052-UEN B
Section 10
Frequency protection
557
Technical manual