ABB Relion 630 Series RET630 Product Manual page 33

ABB
Transformer Protection and Control
RET630
Product version: 1.1
Table 34. Non-directional earth-fault protection (EFxPTOC)
Characteristic
Operation accuracy
1)2)
Start time
Reset time
Reset ratio
Retardation time
Operate time accuracy in definite time mode
Operate time accuracy in inverse time mode
Suppression of harmonics
1) Operate curve type = IEC definite time, Measurement mode = default (depends on stage), current before fault =
0.0 x I , f = 50 Hz, earth-fault current with nominal frequency injected from random phase angle, results based
n n
on statistical distribution of 1000 measurements
2) Includes the delay of the signal output contact
3) Maximum Start value = 2.5 x I
EFLPTOC
EFHPTOC
and
EFIPTOC
EFIPTOC:
I = 2 x set Start
Fault
value
EFHPTOC:
I = 2 x set Start
Fault
value
EFLPTOC:
I = 2 x set Start
Fault
value
, Start value multiples in range of 1.5 to 20
n
Value
At the frequency f = f
n
±1.5% of the set value or ±0.001 x I
±1.5% of set value or ±0.002 x I
(at currents in the range of 0.1...10 x I
±5.0% of the set value
(at currents in the range of 10...40 x I
Typical 12 ms (±5 ms)
Typical 19 ms (±5 ms)
Typical 23 ms (±15 ms)
< 45 ms
Typical 0.96
< 30 ms
±1.0% of the set value or ±20 ms
±5.0% of the theoretical value or ±20 ms
RMS: No suppression
DFT: -50 dB at f = n x f
n
...
Peak-to-Peak: No suppression
1MRS756978 D
Issued: 2011-05-18
n
n
)
n
)
n
3)
, where n = 2, 3, 4, 5,
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