Faulty Merging Unit For Bay In Service - Hitachi Relion 670 Series Applications Manual

Section 19
Station communication
IEC08000069 V2 EN-US
Figure 115:
19.3.2

Faulty merging unit for bay in service

When a merging unit goes faulty while the bay is in service, the protection functions connected to that
merging unit get blocked. Also, protection functions configured in a 1 1/2 circuit breaker applications,
where two SV streams from different merging units are combined get blocked. Thus, this has no effect on
protection functions in a 1 1/2 circuit breaker configuration.
This can be resolved by connecting external binary input signals to the BLOCK input on the respective
SMAI function blocks with the use of ACT. When the BLOCK input on a SMAI function is energized, the
280
Station Wide
SCADA System
Other
Relays
CT
Example of a station configuration with the IED receiving analog values from both
classical measuring transformers and merging units.
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IEC61850-8-1
IEC61850-8-1
110 V
IED
1 A
1 A
IEC61850-9-2LE
Ethernet Switch
IEC61850-9-2LE
ABB
Merging
Unit
Combi
CT
Sensor
Conventional VT
1MRK511407-UUS Rev. N
Station Wide
GPS Clock
Splitter
Electrical-to-
Optical Converter
1PPS
1PPS
en08000069-3.vsd
GUID-CBAB6232-91E6-487C-8C75-7150E2350A6B v2
Phasor measurement unit RES670
Application manual