ABB RELION 615 Series Product Manual page 41

Transformer Protection and Control
RET615
Product version: 5.0 FP1
Table 42. Three-phase thermal overload protection, two time constants (T2PTTR) main settings
Parameter
Temperature rise
Max temperature
Operate temperature
Short time constant
Weighting factor p
Current reference
Operation
Table 43. Stabilized and instantaneous differential protection for two-winding transformers (TR2PTDF)
Characteristic
Operation accuracy
1)2)
Start time
Reset time
Reset ratio
Suppression of harmonics
1) Current before fault = 0.0, f = 50 Hz, results based on statistical distribution of 1000 measurements
n
2) Includes the delay of the output contact. When differential current = 2 × set operate value and f
ABB
Function
T2PTTR
T2PTTR
T2PTTR
T2PTTR
T2PTTR
T2PTTR
T2PTTR
Low stage
High stage
Value (Range)
0.0...200.0°C
0.0...200.0°C
80.0...120.0%
6...60000 s
0.00...1.00
0.05...4.00 × I
n
1 = on
5 = off
Value
Depending on the frequency of the measured current: f
±3.0% of the set value or ±0.002 × I
Minimum Typical
36 ms 41 ms
21 ms 22 ms
Typically 40 ms
Typically 0.96
DFT: -50 dB at f = n × f , where n = 2, 3, 4, 5, ...
n
= 50 Hz.
n
1MRS756891 M
Step
0.1
0.1
0.1
1
0.01
0.01
-
±2 Hz
n
n
Maximum
46 ms
24 ms
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