Table 44. Three-phase overvoltage protection (PHPTOV) main settings
Parameter
Function
Value (Range)
Step
Start value
PHPTOV
0.05...1.60 x U
n
0.01
Time multiplier
PHPTOV
0.05...15.00
0.01
Operate delay time
PHPTOV
40...300000 ms
10
Operating curve type
1)
PHPTOV
Definite or inverse time
Curve type: 5, 15, 17, 18, 19, 20
1)
For further reference, see Operation characteristics table
Table 45. Positive-sequence undervoltage protection (PSPTUV)
Characteristic
Value
Operation accuracy
Depending on the frequency of the voltage measured: f
n
±2 Hz
±1.5% of the set value or ±0.002 x U
n
Start time
1)2)
Minimum
Typical
Maximum
U
Fault
= 0.99 x set
Start value
U
Fault
= 0.9 x set
Start value
51 ms
43 ms
53 ms
45 ms
54 ms
46 ms
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
Suppression of harmonics
DFT: -50 dB at f = n x f
n
, where n = 2, 3, 4, 5,…
1)
Start value = 1.0 x U
n
, Positive sequence voltage before fault = 1.1 x U
n
, f
n
= 50 Hz, positive sequence undervoltage 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 46. Positive-sequence undervoltage protection (PSPTUV) main settings
Parameter
Function
Value (Range)
Step
Start value
PSPTUV
0.010...1.200 x U
n
0.001
Operate delay time
PSPTUV
40...120000 ms
10
Voltage block value
PSPTUV
0.01...1.0 x U
n
0.01
Transformer Protection and Control
1MRS757846 A
RET620
Product version: 2.0
34
ABB
