7.12.8 Technical data
SEMOD175144-2 v9
Table 178: LEXPDIS (40) technical data
Function Range or value Accuracy
X offset of Mho top point for
Zone 1 and Zone 2
(–1000.00–1000.00)% of Z
Base
±5.0% of V
n
/I
n
Diameter of Mho circle for
Zone 1 and Zone 2
(0.0–3000.00)% of Z
Base
±5.0% of V
n
/I
n
Independent time delay for
Zone 1 when impedance jumps
from the outside the set circle
to the center of the set circle
(0.00-6000.00) s ±0.2% or ±60 ms whichever is greater
Independent time delay for
Zone 2 when impedance
jumps from the outside the
set circle to the center of the
set circle
(0.00-6000.00) s ±0.2% or ±60 ms whichever is greater
Trip time, pickup when
impedance jumps from the
outside the set circle to the
center of the set circle
Min. = 35 ms
Max. = 50 ms
-
7.13 Sensitive rotor earth fault protection, injection based
ROTIPHIZ (64R)
GUID-60B5DBE4-5942-471A-95DD-D6077894A8C1 v1
7.13.1 Identification
GUID-BA521452-3BE2-4D63-9FC1-58647166FFD9 v1
Function description IEC 61850
identification
IEC 60617
identification
ANSI/IEEE C37.2
device number
Sensitive rotor earth fault
protection, injection based
ROTIPHIZ Rre< 64R
7.13.2 Functionality
GUID-9D60105D-44C8-4FB1-AD63-C4D3631BC99E v2
The sensitive rotor earth fault protection (ROTIPHIZ, 64R) is used to detect ground faults in the
rotor windings of generators. ROTIPHIZ (64R) is applicable for all types of synchronous
generators.
To implement the above concept, a separate injection box is required. The injection box generates
a square wave voltage signal at a certain preset frequency which is fed into the rotor winding.
The magnitude of the injected voltage signal and the resulting injected current is measured
through a resistive shunt located within the injection box. These two measured values are fed to
the IED. Based on these two measured quantities, the protection IED determines the rotor winding
resistance to ground. The resistance value is then compared with the preset fault resistance alarm
and trip levels.
1MRK 502 066-UUS B Section 7
Impedance protection
395
Technical manual
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