ABB RET615 Product Manual page 39

ABB
Transformer Protection and Control
RET615
Product version: 4.0
Table 36. Three-phase overvoltage protection (PHPTOV)
Characteristic
Operation accuracy
1)2)
Start time
Reset time
Reset ratio
Retardation time
Operate time accuracy in definite time mode
Operate time accuracy in inverse time mode
Suppression of harmonics
1) Start value = 1.0 x U , Voltage before fault = 0.9 x U
n
phase angle, results based on statistical distribution of 1000 measurements
2) Includes the delay of the signal output contact
Start value = 1.20 x U
3) Maximum ,
n
Table 37. Three-phase overvoltage protection (PHPTOV) main settings
Parameter
Start value
Time multiplier
Operate delay time
1)
Operating curve type
1) For further reference please refer to the Operating characteristics table
Start value
U = 1.1 x set
Fault
, f = 50 Hz, overvoltage in one phase-to-phase with nominal frequency injected from random
n n
Start value multiples in range of 1.10 to 2.00
Function
PHPTOV
PHPTOV
PHPTOV
PHPTOV
Value
Depending on the frequency of the voltage measured: f
±2 Hz
±1.5% of the set value or ±0.002 x U
Minimum Typical
22 ms 24 ms
< 40 ms
Relative hysteresis
Depends of the set
< 35 ms
±1.0% of the set value or ±20 ms
±5.0% of the theoretical value or ±20 ms
DFT: -50 dB at f = n x f , where n = 2, 3, 4, 5,...
n
Value (Range)
0.05...1.60 x U
n
0.05...15.00
40...300000 ms
Definite or inverse time
Curve type: 5, 15, 17, 18, 19, 20
1MRS756891 F
n
n
Maximum
26 ms
3)
Step
0.01
0.01
10
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