ABB REL650 series, Техническое руководство

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7.2.6 Monitored Data
Table 81: SPTPIOC (50) Monitored data
Name Type Values (Range) Unit Description
IA REAL - A Current in phase A
IB REAL - A Current in phase B
IC REAL - A Current in phase C
7.2.7 Principle of operation
The sampled analog phase currents are pre-processed in a discrete Fourier filter (DFT)
block. From the fundamental frequency components, as well as sampled values, of each
phase current the RMS value of each phase current is derived. These phase current values
are fed to the Instantaneous phase overcurrent protection phase segregated output
SPTPIOC (50) function. In a comparator the RMS values are compared to the set
operation current value of the function Pickup. If a phase current is larger than the set
operation current a signal from the comparator for this phase is set to true. This signal will,
without delay, activate the output signal
TR_x(x=A, B or C) for this phase and the TRIP
signal that is common for all three phases.
The SPTPIOC (50) function can be blocked from the binary input BLOCK.
7.2.8 Technical data
Table 82: SPTPIOC (50) Technical data
Function Range or value Accuracy
Operate current (5-2500)% of lBase
±
1.0% of I
n
at I
£
I
n
± 1.0% of I at I > I
n
Reset ratio > 95% -
Operate time 20 ms typically at 0 to 2 x I
set
-
Reset time 30 ms typically at 2 to 0 x I
set
-
Critical impulse time 10 ms typically at 0 to 2 x I
set
-
Operate time 10 ms typically at 0 to 5 x I
set
-
Reset time 40 ms typically at 5 to 0 x I
set
-
Critical impulse time 2 ms typically at 0 to 5 x I
set
-
Dynamic overreach < 5% at
t
= 100 ms -
1MRK 506 335-UUS A
Section 7
Current protection
193
Technical manual