Restricted Earth-Fault Protection, Low Impedance Refpdif (87N) - ABB Relion Technical Manual

Section 6
Differential protection
6.2
6.2.1
6.2.2
118
Function
Base sensitivity function
Minimum negative sequence current
Operate angle, negative sequence
Second harmonic blocking
Fifth harmonic blocking
Connection type for each of the windings
Phase displacement between high voltage
winding, W1 and each of the windings, W2
and W3. Hour notation
Operate time, restrained function
Reset time, restrained function
Operate time, unrestrained function
Reset time, unrestrained function
Restricted earth-fault protection, low impedance
REFPDIF (87N)
Identification
Function description
Restricted earth-fault protection, low
impedance
Functionality
Restricted fault protection, low-impedance function REFPDIF (87N)can be used on all
solidly or low-impedance grounded windings. The REFPDIF (87N) function provides
Range or value
IBase
(0.05 - 0.60) x
(0.02 - 0.20) x IBase
(30.0 - 90.0) degrees
(5.0-100.0)% of
fundamental differential
current
(5.0-100.0)% of
fundamental differential
current
Wye or delta
0–11
25 ms typically at 0 to 5
x set level
25 ms typically at 5 to 0
x set level
20 ms typically at 0 to 5
x set level
25 ms typically at 5 to 0
x set level
IEC 61850 IEC 60617
identification identification
REFPDIF
IdN/I
SYMBOL-AA V1 EN
1MRK 502 048-UUS A
Accuracy
± 1.0% of In
± 1.0% of In
± 1.0 degrees
± 2.0% of applied harmonic
magnitude
± 12.0% of applied harmonic
magnitude
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ANSI/IEEE C37.2
device number
87N
Technical manual