Hitachi Relion 670 Series Applications Manual page 285

1MRK511407-UUS Rev. N
SDM600
IEC18000011 V1 EN-US
Figure 114:
The IED can get analog values simultaneously from a classical CT or VT and from a Merging Unit, like in
this example:
The merging units (MU) are called so because they can gather analog values from one or more
measuring transformers, sample the data and send the data over process bus to other clients (or
subscribers) in the system. Some merging units are able to get data from classical measuring
transformers, others from non-conventional measuring transducers and yet others can pick up data from
both types. The electronic part of a non-conventional measuring transducer (like a Rogowski coil or a
capacitive divider) can represent a MU by itself as long as it can send sampled data over process bus.
Phasor measurement unit RES670
Application manual
Maintenance Center Network Control Center
Engineering
Computer HMI
Firewall
Workstation
VPN
AFS 6xx
AFS 6xx
SAM600 SAM600
Example of a station configuration with separated process bus and station bus
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Printer
Events Printer
WAMS
AFS 6xx
Gateway
AFS 6xx
SAM600
Station communication
IEC 6185 0
FOX615
NSD570
IET600 PCM600 ITT600
IEC18000011-1-en.vsdx
Section 19
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