Three-Phase Directional Overcurrent Protection - ABB RET630 Product Manual

Transformer Protection and Control
RET630
Product version: 1.0
Table 29. Three-phase directional overcurrent protection (DPHxPDOC)
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) Measurement mode = default (depends of stage), current before fault = 0.0 x I
phase 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
26
DPHLPDOC
DPHHPDOC
I = 2.0 x set Start
Fault
value
, Start value multiples in range of 1.5 to 20
n
Value
At the frequency f = f
n
Current:
±1.5% of the set value or ±0.002 x I
Voltage:
±1.5% of the set value or ±0.002 x U
Phase angle:
±2°
Current:
±1.5% of the set value or ±0.002 x I
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 )
n
Voltage:
±1.5% of the set value or ±0.002 x U
Phase angle:
±2°
Typical: 24 ms (±15 ms)
< 40 ms
Typical 0.96
< 35 ms
±1.0% of the set value or ±20 ms
±5.0% of the theoretical value or ±20 ms
RMS: No suppression
DFT: -50dB at f = n x f
n
...
Peak-to-Peak: No suppression
P-to-P+backup: No suppression
, f = 50 Hz, fault current in one
n n
1MRS756788 A
Issued: 15.09.2009
n
n
(at
n
)
n
n
3)
, where n = 2, 3, 4, 5,
ABB