ABB RET630 - Positive Sequence Undervoltage Protection

Table 51. Positive sequence undervoltage protection (PSPTUV)
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
= 0.9 x set Start
value
Typical 28 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 = 1.1 × U
n
, f
n
= 50 Hz, residual voltage with nominal frequency injected from
random phase angle
2) Includes the delay of the signal output contact
Table 52. Positive sequence undervoltage protection (PSPTUV) main settings
Parameter
Function Value (Range) Step
Start value PSPTUV 0.010...1.200 pu 0.001
Operate delay time PSPTUV 0.040...120.000 s 0.001
Voltage block value PSPTUV 0.01...1.0 pu 0.01
Transformer Protection and Control 1MRS756788 A
RET630
Product version: 1.0 Issued: 15.09.2009
ABB 39