3U0 > 3U0>
AND
t
tUN
startUPP
t
tIN
t
tOffUN
OR
OR
(Non delayed IN start)
IEC16000018-1-en.vsdx
3I0>IN>
startIN
IEC16000018 V1 EN-US
Figure 71: Residual current criteria
6.5.6.2 Phase selection
GUID-A3B9F4A9-30D1-40E5-B0A8-6BB66093C27A v1
During a cross-country fault, the phase with an external fault typically does not
carry any fault current, which will make it difficult for a conventional phase
selection function to detect the fault. Therefore, PPL2PHIZ function provides an
additional phase selection based on voltage.
PPL2PHIZ is designed to detect two-phase faults based on under-voltage in two
phases or between two phases.
OR
startU
ULxLy < UPP<
L3L1
L2L3
L1L2
ULx < UPN<
L3
L2
L1
3U0 > 3U0>
AND
AND
AND
OR
OR
OR
AND
startUL1
startUL2
startUL3
OR
OR
OR
startUL1L2
startUL2L3
startUL3L1
IEC16000019-1-en.vsdx
IEC16000019 V1 EN-US
Figure 72: Phase selection
The voltage phase selection can be complemented with external phase selection
through inputs RELL1-3N.
Voltage phase selection is disabled in
No Filter and NoPref
operating modes.
Section 6 1MRK 506 382-UEN A
Impedance protection
152 Line distance protection REL650 2.2 IEC
Technical manual