ABB RET620 - Transformer Differential Protection for Two-Winding Transformers (TR2 PTDF); Stabilized Differential Protection for Two-Winding Transformers (TR2 PTDF) Main Settings

Table 55. Transformer differential protection for two-winding transformers (TR2PTDF)
Characteristic Value
Operation accuracy At the frequency f = f
n
±1.5% of the set value or ±0.002 × I
n
Operate time
1)2)
Biased low stage
Instantaneous high stage
Typical 35 ms (±5 ms)
Typical 17 ms (±5 ms)
Reset time < 30 ms
Reset ratio Typical 0.96
Retardation time < 35 ms
Suppression of harmonics DFT: -50 dB at f = n x f
n
, where n = 2, 3, 4, 5,…
1) Differential current before fault = 0.0 × I
n
, f
n
= 50 Hz. Injected differential current = 2.0 × set operate value
2) Includes the delay of the output contact value and f
n
= 50 Hz
Table 56. Stabilized differential protection for two-winding transformers (TR2PTDF) main settings
Parameter Function Value (Range) Step
Restraint mode TR2PTDF 2.h & 5.h & wav
Waveform
2.h & waveform
5.h & waveform
-
High operate value TR2PTDF 500...3000 % 10
Low operate value TR2PTDF 5...50 % 1
Slope section 2 TR2PTDF 10...50 % 1
End section 2 TR2PTDF 100...500 % 1
Start value 2.H TR2PTDF 7...20 % 1
Start value 5.H TR2PTDF 10...50 % 1
Operation TR2PTDF Off
On
-
Winding 1 type TR2PTDF Y
YN
D
Z
ZN
-
Winding 2 type TR2PTDF Y
YN
D
Z
ZN
-
Zro A elimination TR2PTDF Not eliminated
Winding 1
Winding 2
Winding 1 and 2
-
Transformer Protection and Control 1MRS757846 A
RET620
Product version: 2.0
ABB 37