Table 45. Three-phase overvoltage protection (PHPTOV)
Characteristic Value
Operation accuracy At the frequency f = f
n
±1.5% of the set value or ±0.002 × U
n
Start time
1)2)
U
Fault
= 2.0 x set Start
value
Typical 17 ms (±15ms)
Reset time < 40 ms
Reset ratio
Depends of the set Relative hysteresis
Retardation time < 35 ms
Operate time accuracy in definite time mode ±1.0% of the set value or ±20 ms
Operate time accuracy in inverse time mode
±5.0% of the theoretical value or ±20 ms
3)
Suppression of harmonics DFT: -50 dB at f = n × f
n
, where n = 2, 3, 4, 5,
…
1)
Start value = 1.0 × U
n
, Voltage before fault = 0.9 × U
n
, f
n
= 50 Hz, overvoltage in one phase-to-phase with
nominal frequency injected from random phase angle
2) Includes the delay of the signal output contact
3)
Maximum Start value = 1.20 × U
n
, Start value multiples in range of 1.10 to 2.00
Table 46. Three-phase overvoltage protection (PHPTOV) main settings
Parameter
Function Value (Range) Step
Start value PHPTOV 0.05...1.60 pu 0.01
Time multiplier PHPTOV 0.05...15.00 0.05
Operate delay time PHPTOV 0.40...300.000 s 0.10
Operating curve
type
1)
PHPTOV Definite or inverse time
Curve type: 5, 15, 17, 18, 19, 20
1) For further reference please refer to the Operating characteristics table
Transformer Protection and Control 1MRS756788 A
RET630
Product version: 1.0 Issued: 15.09.2009
36 ABB
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