ABB REF630 - Negative Sequence Overvoltage Protection (NSPTOV); Negative Sequence Overvoltage Protection (NSPTOV) Main Settings

Table 53. Negative sequence overvoltage protection (NSPTOV)
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
= 1.1 x set
Start value
U
Fault
= 2.0 x set
Start value
Typical 29 ms (±15ms)
Typical 24 ms (±15ms)
Reset time < 40 ms
Reset ratio Typical 0.96
Retardation time < 35 ms
Operate time accuracy in definite time mode ±1.0% of the set value or ±20 ms
Suppression of harmonics DFT: -50 dB at f = n × f
n
, where n = 2, 3, 4, 5,
…
1) Residual voltage before fault = 0.0 × U
n
, f
n
= 50 Hz, residual overvoltage with nominal frequency injected from
random phase angle
2) Includes the delay of the signal output contact
Table 54. Negative sequence overvoltage protection (NSPTOV) main settings
Parameter
Function Value (Range) Step
Start value NSPTOV 0.010...1.000 pu 0.001
Operate delay time NSPTOV 0.040...120.000 s 0.001
Feeder Protection and Control 1MRS756380 A
REF630
Product version: 1.0 Issued: 15.09.2009
42 ABB