GEK-98846A
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4.6 REMOTE OPEN DETECTOR UNIT (ROD) (MLP3000)
The remote open detector unit operates when the breaker on the remote side
opens during an unbalanced internal fault. This characteristic allows the accelerated
isolation of faults. In the absence of this unit, a sequential trip will be provoked.
In this Way it allows a rapid trip in the local extreme, for faults inside the line but
outside zone 1 reach without using a communications carrier. For example, let's see how a
fault is cleared in 95% of the line:
The local relay will detect the fault in zone 3 and start the zone 3 and zone 2 timers.
Meanwhile the remote extreme detects the fault in zone 1 and orders a trip. When the
remote breaker has been opened, it is detected by the local relay and once the ROD timing
has terminated a remote open detector trip is performed.
We need to keep in mind that if the tripping time plus the time to open the remote
breaker plus the ROD timing is greater then the zone 2 timing, the local relay will perform a
zone 2 trip and not a ROD trip. For ROD timing keep in mind that ROD units as well as
distance measuring units take 1 cycle to operate.
This unit does not work for three phase faults, since the information to detect that
the remote extreme is open reaches the local extreme through a vectoral change of t]1C
line current in any of the "healthy" phases.
Figures 8.1 and 8.2 illustrate the algorithm for remote open pole detection. This
algorithm is based on the fact that the impedance of a "healthy" line whose extreme remote
is open is purely capacitive.
4.7. DISTURBANCE DETECTION UNIT (DD) (MLP3000)
This function assists in the detection of a fuse failure and the starting of the
oscillographic register. Its purpose is to detect faults before they are detected by the
distance measuring units, based on the detection of the fault positive sequence current.
Figures 9.1 and 9.2 illustrate the algorithm for disturbance detection.
Summary of Contents for MLP1000
Page 94: ...GEK 98846A 93 Figure 1 System diagram with MLP CPR and TTI ...
Page 95: ...GEK 98846A 94 Figure 2 Case dimensions and drilling form 1 rack ...
Page 96: ...GEK 98846A 95 Figure 3 1 External Connections MLP1000 ...
Page 97: ...GEK 98846A 96 Figure 3 2 External Connections MLP1000 ...
Page 99: ...GEK 98846A 98 Figure 3 4 External Connections MLP1000 ...
Page 100: ...GEK 98846A 99 Figure 3 5 External Connections MLP2000 ...
Page 101: ...GEK 98846A 100 Figure 3 6 External Connections MLP2000 ...
Page 103: ...GEK 98846A 102 Figure 3 8 External Connections MLP2000 ...
Page 104: ...GEK 98846A 103 Figure 3 9 External Connections MLP3000 ...
Page 105: ...GEK 98846A 104 Figure 3 10 External Connections MLP3000 ...
Page 107: ...GEK 98846A 106 Figure 3 12 External Connections MLP3000 ...
Page 108: ...GEK 98846A 107 Figure 4 Protection Logic ...
Page 109: ...GEK 98846A 108 Figure 5 1 Trip decision diagram ...
Page 110: ...GEK 98846A 109 Figure 5 2 Trip decision diagram ...
Page 111: ...GEK 98846A 110 Figure 5 3 Trip decision diagram ...
Page 112: ...GEK 98846A 111 Figure 5 4 Trip decision diagram ...
Page 113: ...GEK 98846A 112 Figure 6 1 Z1X protection scheme ...
Page 114: ...GEK 98846A 113 Figure6 2 ACCZ2 Protection scheme ...
Page 115: ...GEK 98846A 114 Figure7 LPU function diagram ...
Page 116: ...GEK 98846A 115 Figure 8 1 ROD function logic ...
Page 117: ...GEK 98846A 116 Figure 8 2 ROD function diagram ...
Page 118: ...GEK 98846A 117 Figure 9 1 DD function logic ...
Page 119: ...GEK 98846A 118 Figure 9 2 DD function diagram ...
Page 120: ...GEK 98846A 119 Figure 10 1 FF function logic ...
Page 121: ...GEK 98846A 120 Figure 10 2 FF function diagram ...
Page 122: ...GEK 98846A 121 Figure 11 1 Recloser diagram ...
Page 123: ...GEK 98846A 122 Figure 11 2 Recloser Diagram ...
Page 124: ...GEK 98846A 123 Figure 11 3 Recloser Diagram ...
Page 125: ...GEK 98846A 124 Figure 12 Fault selector ...
Page 126: ...GEK 98846A 125 Figure 13 Menu Tree Diagram ...
Page 127: ...GEK 98846A 126 Figure 14 MLP3000 Settings and data ...
Page 128: ...GEK 98846A 127 Figure 15 Connection scheme for relay tests ...
Page 129: ...GEK 98846A 128 Figure 16 Power swing diagram function ...
Page 130: ...GEK 98846A 129 Figure 17 Mho Reactance characteristics of the MLP ...