ABB REX640 - Frequency Protection (FRPFRQ); Negative-Sequence Overvoltage Protection (NSPTOV) Main Settings; Negative-Sequence Overvoltage Protection (NSPTOV)

Table 88. Negative-sequence overvoltage protection (NSPTOV)
Characteristic Value
Operation accuracy Depending on the frequency of the voltage measured: f
n
±1.5% of the set value or ±0.002 × U
n
Start time
1)2)
Minimum Typical Maximum
U
Fault
= 1.1 × set Start value
U
Fault
= 2.0 × set Start value
33 ms
24 ms
35 ms
26 ms
37 ms
28 ms
Reset time Typically 40 ms
Reset ratio Typically 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) Negative-sequence voltage before fault = 0.0 × U
n
, f
n
= 50 Hz, negative-sequence overvoltage with nominal frequency injected from random phase angle, results based on statistical
distribution of 1000 measurements
2) Includes the delay of the signal output contact
Table 89. Negative-sequence overvoltage protection (NSPTOV) main settings
Parameter
Function Value (Range) Step
Start value NSPTOV 0.010...1.000 × U
n
0.001
Operate delay time NSPTOV 40...120000 ms 1
Table 90. Frequency protection (FRPFRQ)
Characteristic
Value
Operation accuracy f>/f< ±5 mHz
df/dt ±50 mHz/s (in range |df/dt| <5 Hz/s)
±2.0% of the set value (in range 5 Hz/s < |df/dt| < 15 Hz/s)
Start time f>/f< <80 ms
df/dt <120 ms
Reset time <150 ms
Operate time accuracy ±1.0% of the set value or ±30 ms
1MRS759144 A
REX640
Product version: 1
ABB 57