Technical Data - ABB Relion Technical Manual

Section 9
Voltage protection
9.5.8
318
With the circuit breaker open, the total capacitance will be smaller compared to normal
operating conditions. This means that the neutral point 3
reduced compared to the normal operating condition. Therefore, there is a possibility to
reduce the sensitivity of the protection when the generator circuit breaker is open.
With the setting CBexists change of the sensitivity is enabled. If the binary input signal 52a
is activated the set sensitivity is valid. If the generator circuit breaker is opened the binary
input 52a is deactivated and the sensitivity is changed. This is done by changing the factor
Beta which is multiplied with a set constant FactorCBopen.
In addition to the binary outputs also some analog outputs are available from the
protection function in order to enable easier commissioning:
E3: the magnitude of the 3
VN3: the magnitude of the 3
generator
VT3: the magnitude of the 3
generator
ANGLE: the angle between the phasors VN3 and VT3 given in radians
DV3: the magnitude of the 3
BV3: the magnitude of the 3
V_N: the fundamental frequency voltage measured in the neutral point of the generator

Technical data

Table 183: STEFPHIZ (59THD) technical data
Function
Fundamental frequency level UN
(95% Stator EF)
Third harmonic differential level
Third harmonic differential block
level
Timers
Filter characteristic:
Fundamental
Third harmonic
rd
harmonic voltage induced in the stator given in primary volts
rd
harmonic voltage measured in the neutral point of the
rd
harmonic voltage measured in the terminal point of the
rd
harmonic differential voltage
rd
harmonic bias voltage
Range or value
VBase
(1.0–50.0)% of
(0.5–10.0)% of VBase
VBase
(0.1–10.0)% of
(0.020–60.000) s
Reject third harmonic by 1–40
Reject fundamental harmonic by
1–40
1MRK 502 048-UUS A
rd
harmonic voltage will be
Accuracy
± 0.5% of V
n
± 5.0% of V
n
± 5.0% of V
n
± 0.5% ± 25 ms
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Technical manual