Negative Sequence Time Overcurrent Protection For Machines Ns2Ptoc - ABB RET670 Product Manual

Transformer protection RET670 2.0
Product version: 2.0
Table 56. Negative sequence time overcurrent protection for machines NS2PTOC
Function
Operate current, step 1 - 2
Reset ratio
Operate time, start at 0 to 2 x I
Reset time, start at 2 to 0 x I
Operate time, start at 0 to 10 x I
Reset time, start at 10 to 0 x I
Time characteristics
Inverse time characteristic, step 1 - 2
2
=
I t K
2
Reset time, inverse characteristic,
step 1 - 2
2
=
I t K
2
Minimum operate time for inverse time
characteristic, step 1 - 2
Maximum trip delay at 0.5 to 2 x I
step 1 - 2
Independent time delay at 0.5 to 2 x
I , step 1 - 2
set
Independent time delay for Alarm at
0.5 to 2 x I
set
ABB
Range or value
(3-500)% of IBase
>95%
Min. = 15 ms
set
Max. = 30 ms
Min. = 15 ms
set
Max. = 30 ms
Min. = 5 ms
set
Max. = 20 ms
Min. = 20 ms
set
Max. = 35 ms
Definite or Inverse
K=1.0-99.0
Reset Multiplier = 0.01-20.00
(0.000-60.000) s
, (0.00-6000.00) s
set
(0.00-6000.00) s
(0.00-6000.00) s
Accuracy
±1.0% of I at I ≤ I
r r
±1.0% of I at I > I
r
-
-
-
-
-
-
±2.0% or ±40 ms whichever is
greater
±5.0% or ±40 ms whichever is
greater
±0.2% or ±35 ms whichever is
greater
±0.2% or ±35 ms whichever is
greater
±0.2% or ±35 ms whichever is
greater
±0.2% or ±35 ms whichever is
greater
1MRK 504 141-BEN C
71