Table 158. Numerical stabilized low-impedance restricted earth-fault protection (LREFPNDF) main settings
Parameter
Function
Value (Range)
Step
Operate value
LREFPNDF
5.0...50.0 %I
n
1
Minimum operate time
LREFPNDF
40...300000 ms
1
Restraint mode
LREFPNDF
1 = None
2 = Harmonic2
-
Start value 2.H
LREFPNDF
10...50%
1
Operation
LREFPNDF
1 = on
5 = off
-
Table 159. High-impedance based restricted earth-fault protection (HREFPDIF)
Characteristic
Value
Operation accuracy
Depending on the frequency of the measured current: f
n
±2 Hz
±1.5% of the set value or ±0.002 × I
n
Start time
1)2)
Minimum
Typical
Maximum
I
Fault
= 2.0 × set
Operate value
I
Fault
= 10.0 × set
Operate value
16 ms
11 ms
21 ms
13 ms
23 ms
14 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
1)
Current before fault = 0.0, f
n
= 50 Hz, results based on statistical distribution of 1000 measurements
2)
Includes the delay of the signal output contact
Table 160. High-impedance based restricted earth-fault protection (HREFPDIF) main settings
Parameter
Function
Value (Range)
Step
Operate value
HREFPDIF
1.0...50.0 %I
n
0.1
Minimum operate time
HREFPDIF
40...300000 ms
1
Operation
HREFPDIF
1 = on
5 = off
-
1MRS759144 A
REX640
Product version: 1
ABB
79
Содержание RELION REX640
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