ABB RELION 670 Series Product Manual page 79

Transformer protection RET670 2.1 IEC
Table 52. Four step negative sequence overcurrent protection NS4PTOC
Function
Operate current, step 1 - 4
Reset ratio
Independent time delay at 0
to 2 x I , step 1 - 4
set
Minimum operate time for
inverse curves, step 1 - 4
Inverse time characteristics,
see table 157, table 158 and
table 159
Minimum operate current,
step 1 - 4
Relay characteristic angle
(RCA)
Operate current for
directional release
Minimum polarizing voltage
Minimum polarizing current
Real part of negative
sequence source impedance
used for current polarization
Imaginary part of negative
sequence source impedance
used for current polarization
Operate time, start non-
directional at 0 to 2 x I
set
Reset time, start non-
directional at 2 to 0 x I
set
Operate time, start non-
directional at 0 to 10 x I
set
Reset time, start non-
directional at 10 to 0 x I
set
Critical impulse time
Impulse margin time
Transient overreach
ABB
GUID-E83AD807-8FE0-4244-A50E-86B9AF92469E v5
Range or value
lBase
(1-2500)% of
> 95% at (10-2500)% of IBase
(0.000-60.000) s
(0.000 - 60.000) s
16 curve types
IBase
(1.00 - 10000.00)% of
(-180 to 180) degrees
IBase
(1–100)% of
(1–100)% of UBase
IBase
(2-100)% of
(0.50-1000.00) W/phase
(0.50–3000.00) W/phase
Min. = 15 ms
Max. = 30 ms
Min. = 15 ms
Max. = 30 ms
Min. = 5 ms
Max. = 20 ms
Min. = 20 ms
Max. = 35 ms
10 ms typically at 0 to 2 x I
set
15 ms typically
<10% at τ = 100 ms
1MRK 504 155-BEN F
Accuracy
±1.0% of I at I £ I
r r
±1.0% of I at I > I
r
-
±0.2% or ±35 ms whichever is
greater
±0.2% or ±35 ms whichever is
greater
See table 157, table 158 and
table 159
±1.0% of I at I ≤ I
r r
±1.0% of I at I > I
r
±2.0 degrees
For RCA ±60 degrees:
±2.5% of I at I ≤ I
r r
±2.5% of I at I > I
r
±0.5% of U
r
±1.0% of I
r
-
-
-
-
-
-
-
-
-
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