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en06000519-2.vsd
IEC06000519 V2 EN
Figure 413: Direct fibre optical connection between two IEDs with LDCM
The LDCM can also be used together with an external optical to galvanic G.703 converter
as shown in figure 414. These solutions are aimed for connections to a multiplexer, which
in turn is connected to a telecommunications transmission network (for example PDH).
Telecom. Network
*) *)
Multiplexer Multiplexer
en05000527-2.vsd
*) Converting optical to galvanic G.703
IEC05000527 V2 EN
Figure 414: LDCM with an external optical to galvanic converter and a multiplexer
When an external modem G.703 is used, the connection between LDCM and the modem
is made with a multimode fibre of max. 3 km/2 mile length. The IEEE/ANSI C37.94
protocol is always used between LDCM and the modem.
22.1.3 Setting guidelines
64 kbit and 2 Mbit mode common settings
1MRK 506 369-UUS - Section 22
Remote communication
Line distance protection REL670 2.2 ANSI 885
Application manual