Non-directional current protection – Rockwell Automation 865 Differential Protection Relay User Manual
Page 176
10-6 Technical
Data
865-UM001A-EN-P – July 2009
Non-directional
Current
Protection
Table 10.17 – Overcurrent Stage I>, I’> (50/51)
Pick-up current
0.10 – 5.00 x I
mode
Definite time function:
DT
- Operating time
0.08
– 300.00 s (step 0.02 s)
IDMT function:
- Delay curve family
(DT), IEC, IEEE, RI Prg
- Curve type
EI, VI, NI, LTI, MI…depends on the family
- Time multiplier k
0.05 – 20.0, except
0.50 – 20.0 for RXIDG, IEEE and IEEE2
Start time
Typically 60 ms
Reset time
<95 ms
Retardation time
<50 ms
Reset ratio
0.97
Transient over-reach, any
τ
<10 %
Inaccuracy:
- Starting
±3% of the set value
- Operating time at definite time function
±1% or ±30 ms
- Operating time at IDMT function
±5% or at least ±30 ms
EI = Extremely Inverse, NI = Normal Inverse, VI = Very Inverse, LTI = Long Time Inverse
MI= Moderately Inverse
This is the instantaneous time i.e. the minimum total operational time including the fault
detection time and operation time of the trip contacts.
Table 10.18 – Overcurrent Stages I>> and I’>> (50/51)
Pick-up current
0.10 – 20.00 x I
mode
(I>>)
Definite time function:
0.04
– 300.00 s (step 0.01 s)
- Operating time
Start time
Typically 60 ms
Reset time
<95 ms
Retardation time
<50 ms
Reset ratio
0.97
Transient over-reach, any
τ
<10 %
Inaccuracy:
- Starting
±3% of the set value
- Operation time
±1% or ±25 ms
This is the instantaneous time i.e. the minimum total operational time including the fault
detection time and operation time of the trip contacts.