Function Block; Functionality; Analog Channel Configuration - ABB RELION REX640 Technical Manual

Section 4
Protection functions
4.2.8.2
4.2.8.3
4.2.8.4
510

Function block

GUID-8AAC9755-B961-47F2-8EEA-D4915B3336FF V2 EN
Figure 279: Function block

Functionality

The third harmonic-based stator earth-fault protection H3EFPSEF is used to detect
stator earth fault at the neutral point and at least up to 15...20% from the neutral point
along the stator winding. H3EFPSEF compares the third harmonic voltages produced
by the generator itself at both neutral and terminal side of the generator for detecting
earth fault.
H3EFPSEF provides two alternative protection methods:
• Differential of the third harmonic component measured both at generator neutral
and terminal side
• Neutral side third harmonic undervoltage
H3EFPSEF operates with the definite time DT characteristics.
H3EFPSEF contains a blocking functionality. Blocking deactivates all outputs and
reset timers.

Analog channel configuration

H3EFPSEF has three analog group inputs which must be properly configured.
Table 548: Analog inputs
Input
1)
U3P
2)
URES
UNEUT
1) Can be connected to GRPOFF if
2) Can be connected to GRPOFF if
Description
Three-phase voltages
Necessary when
"Phase A", "Phase B" or "Phase C"
Residual voltage (measured or calculated)
Necessary when
Residual voltage (measured or calculated)
Voltage selection is set to "No voltage" or "Uo"
Voltage selection is other than "Uo"
1MRS759142 C
Voltage selection is set to "Uo",
Voltage selection is set to "Uo"
REX640
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