1. For a particular value of
Beta
the third harmonic neutral voltage is measured
with the generator in the no-load condition and the circuit breaker in the closed
position.
2. With the same condition, the third harmonic neutral voltage with the circuit
breaker in the open position is measured.
3.
CB Open factor
should be set equal to the ratio of the third harmonic neutral
voltage measured with the circuit breaker in the closed position to that in the
open.
4.2.8.7 Signals
H3EFPSEF Input signals
Table 604: H3EFPSEF Input signals
Name Type Default Description
U3P SIGNAL - Three-phase voltages
URES SIGNAL - Residual voltage
UNEUT SIGNAL - Analog input
BLOCK BOOLEAN 0=False Block signal for acti-
vating the blocking
mode
GCB_CLOSED BOOLEAN 0=False Generator CB in
closed position
H3EFPSEF Output signals
Table 605: H3EFPSEF Output signals
Name Type Description
OPERATE BOOLEAN Operate
START BOOLEAN Start
INT_BLKD BOOLEAN Protection internally blocked
4.2.8.8 H3EFPSEF Settings
Table 606: H3EFPSEF Group settings (Basic)
Parameter
Values (Range) Unit Step Default Description
Beta 0.50...10.00 0.01 3.00 Portion of neutral
side 3rd harmonic
used as bias
Voltage N 3.H Lim 0.005...0.200 xUn 0.001 0.010 Start value for 3rd
harmonic residual
undervoltage pro-
tection
Operate delay time 20...300000 ms 10 20 Operate delay time
1MRS759142 F Protection functions
REX640
Technical Manual
551
To Next Page
Loading...
