1. Set DirModeZ4 to Reverse.
2. Set MhoCharZ4 to Directional, if CharPGZ4 or CharPPZ4 is set to Mho.
3. Set Z1 to 4.2 Ω
Z1 = 0.85 · Z
Line, posseq
= 0.85 · 0.28 · 17.5 = 4.2 Ω
4. Set RFPP4 to 4 Ω, if CharPPZ4 is set to Quadrilateral.
Setting RFPP4 ≈ Z4 is proposed
5. Set RFPG4 to 8 Ω, if CharPGZ4 is set to Quadrilateral.
RFPE4 ≈ 2 · Z4 setting is proposed (should never be larger than 4.5 · X4 where X4
is the reactive part of Z4)
6. Set OpModetPGZ4 to Enabled.
Zone 4 phase to earth loop gives trip.
7. Set OpModetPPZ4 to Enabled.
Zone 4 phase to phase loop gives trip.
8. Set time delays to trip
8.1. Set tPPZ4 to 0.400 s
Zone 4 phase to phase loop gives trip after a short delay.
8.2. Set tPGZ4 to 0.400 s
Zone 4 phase to ground loop gives trip after a short delay.
The time delay for zone 4 need margin to assure selectivity to zone 1 of lines out from
substation A. A delay time difference of 0.4 s between the zones is sufficient.
3.1.4 Calculating settings for phase selection with load encroachment
FDPSPDIS (21)
Correct phase selection for faults within zone 1 and 2 is required.
1. Set GlobalBaseSel to 1
2. Set the minimum apparent resistance during non-faulted conditions:
2.1. Set RLdFwd to 70 Ω
2.2. Set RldRev to 70 Ω
The minimum apparent resistance during non-faulted conditions is calculated as:
( )
2
2
min
,max
0.9 138
, Re 0.8 85.7
180
ext
V
RLdFwd Rld v
P
×
£ × = = W
GUID-0428FFD5-8487-414F-9974-E21565F520DA-ANSI V1 EN (Equation 17)
3. Set LdAngle to 30º
It is normally considered that the apparent impedance during non-faulted condition
has a phase angle in the range ± 30º.
4. Set the zero and positive sequence reactance reach
4.1. Set X1 to 50 Ω
1MRK 506 334-UUS A Section 3
REL650 setting examples
55
Application manual
To Next Page
Loading...
