Table 32. Three-phase directional overcurrent protection (DPHxPDOC) main settings
Parameter
Function
Value (Range)
Step
Start value
DPHLPDOC
0.05...5.00 x In
0.01
DPHHPDOC
0.10...40.00 x In
0.01
Time multiplier
DPHxPDOC
0.05...15.00
0.01
Operate delay time
DPHxPDOC
40...200000 ms
10
Directional mode
DPHxPDOC
1 = Non-directional
2 = Forward
3 = Reverse
Characteristic angle
DPHxPDOC
-179...180 deg
1
Operating curve type
1)
DPHLPDOC
Definite or inverse time
Curve type: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19
DPHHPDOC
Definite or inverse time
Curve type: 1, 3, 5, 9, 10, 12, 15, 17
1)
For further reference, refer to the Operating characteristics table
Table 33. Non-directional earth-fault protection (EFxPTOC)
Characteristic
Value
Operation accuracy
Depending on the frequency of the current measured: f
n
±2 Hz
EFLPTOC
±1.5% of the set value or ±0.002 x I
n
EFHPTOC
and
EFIPTOC
±1.5% of set value or ±0.002 x I
n
(at currents in the range of 0.1…10 x I
n
)
±5.0% of the set value
(at currents in the range of 10…40 x I
n
)
Start time
1)2)
Minimum
Typical
Maximum
EFIPTOC:
I
Fault
= 2 x set
Start value
I
Fault
= 10 x set
Start value
16 ms
11 ms
19 ms
12 ms
23 ms
14 ms
EFHPTOC and EFLPTOC:
I
Fault
= 2 x set
Start value
22 ms
24 ms
25 ms
Reset time
< 40 ms
Reset ratio
Typical 0.96
Retardation time
< 30 ms
Operate time accuracy in definite time mode
±1.0% of the set value or ±20 ms
Operate time accuracy in inverse time mode
±5.0% of the theoretical value or ±20 ms
3)
Suppression of harmonics
RMS: No suppression
DFT: -50 dB at f = n x f
n
, where n = 2, 3, 4, 5,…
Peak-to-Peak: No suppression
1)
Measurement mode = default (depends on stage), current before fault = 0.0 x I
n
, f
n
= 50 Hz, earth-fault current 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
3)
Maximum
Start value = 2.5 x I
n
,
Start value multiples in range of 1.5 to 20
Transformer Protection and Control
1MRS757846 A
RET620
Product version: 2.0
28
ABB