ABB
14
GUID-89A9F7DF-FB82-4E8D-B449-7C0BB51C1DCA V1 EN
1MDB07207-YN
Feeder Protection
REF601
Product version: 2.0
Table 23. Low-set earth-fault protection, stage I
o
> / 51N
Parameter
Value (Range)
Internal earth measurement : 0.2...1.0 x I
n
in steps 0.05, infi nite
Operation accuracy
External earth measurement :
±
5.0% of set value
Operate time delay (DMT) ‘t
o
>’ 0.1...1.6 sec in steps of 0.1 for B=1
0.5...8.0 sec in steps of 0.5 for B=5
Operation time accuracy
External earth measurement :
±
5.0% of set value or
±
30 msec
Operating curve type
Normal inverse, Very inverse, Extremely inverse, Long-time inverse
IEC 60255-3:
Special curves:
RI inverse
Time multiplier setting ‘k’
0.1...1.6, in steps of 0.1
Operation time accuracy
External earth measurement : class E(5) or
±
30 msec
External earth measurement : class E(7.5) or
±
30 msec
IEC characteristics
RI characteristics
Reset ratio
IDMT : 0.96 and DT : 0.98
Table 24. High-set earth-fault protection, stage I
o
>> / 50N
Parameter
Value (Range)
Setting range of pick-up current ‘I
o
>>’
0.5...4.0 x I
n
in steps 0.25, infi nite
Operation accuracy
External earth measurement :
±
5.0% of set value
Operation mode
Defi nite time
Operation time accuracy
External earth measurement :
±
5.0% of set value or
±
30 msec
Reset ratio
0.98
Operate time delay (DMT) ‘t
o
>>’
0.00...0.75 sec in steps of 0.05
Nominal value of earth current
1 A
Measurement range
0.05...5 x I
n
Setting range of pick-up current ‘I
o
>’
External earth measurement : 0.05...0.1 x I
n
in steps 0.05, infi nite
Internal earth measurement :
±
15.0% of set value
Internal earth measurement :
±
10.0% of set value or
±
30 msec
Internal earth measurement :
±
5.0% of set value or
±
30 msec
Internal earth measurement :
±
10.0% of set value or
±
30 msec
IEC characteristics
RI characteristics
Internal earth measurement :
±
15.0% of set value
Internal earth measurement :
±
10.0% of set value or
±
30 msec
For setting 0.00 msec : 45 msec
Содержание REF601
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