x/EN FD/Na7
-
MiCOM P74
one of three physical links; K-Bus, EIA(RS)485 or EIA(RS)232. The port supports full local or
remote protection and control access by S1 software. The second rear port is also available
with an on board IRIG-B input (P741).
The optional board also houses port “SK5”, the EIA232 InterMiCOM teleprotection port.
InterMiCOM permits end-to-end signaling with a remote InterMiCOM relay, for example in a
distance protection channel aided scheme. Port SK5 has an EIA(RS)232 connection,
allowing connection to a MODEM, or compatible multiplexers.
All modules are connected by a parallel data and address bus that allows the processor board to
send and receive information to and from the other modules as required. There is also a
separate serial data bus for conveying sample data from the input module to the processor.
1.1.9 Ethernet or redundant Ethernet board (P741 and P743)
Ethernet and redundant Ethernet boards are mandatory boards for IEC 61850 enabled
relays. The boards provide network connectivity through either copper or fiber media at rates
of 10Mb/s (copper only) or 100Mb/s. There is also an option on the Ethernet board (P741) to
specify IRIG-B board port (modulated or un-modulated).
These boards and the second rear comms. board are mutually exclusive as they both utilize
the same within the relay case.
The redundant Ethernet board option (see P4x4/EN REB user guide) provides a redundant
connection, useful to safe exchanges between two relays or for specific network
applications. The different options use SHP, RSTP or DHP protocol, with IRIG B (modulated
or un-modulated) port.
All modules are connected by a parallel data and address bus that allows the processor board to
send and receive information to and from the other modules as required. There is also a
separate serial data bus for conveying sample data from the input module to the processor.
Figure 1 shows the modules of the relay and the flow of information between them.
In the P741 and P743, a dedicated slot is available to receive the optional Ethernet board.
Note: It is possible to connect to the Ethernet network any of the P74x
without the embedded Ethernet board using the RS485 to Ethernet
converter I4X (Courier protocol)
1.2 Software overview
The busbar protection is a distributed system composed of two different software: the first
one is used in central unit (P741) and the second one in peripheral units (P742 & P743).
The software for the relay can be conceptually split into five elements; the real-time
operating system, the system services software, the platform software, the communication
software, and the protection and control software. These five elements are not
distinguishable to the user, and are all processed. The distinction between the five parts of
the software is made purely for the purpose of explanation here: