Settings And Operations; Overview; Connection In C37.94 At St Connectors - Toshiba GR 200 Series Instruction Manual

Settings and operations

2
Figure 2.1-1 shows the outline of the GIF200 unit. Two optical modules (E/O and O/E with ST
port) for the IEEE C37.94 and a CN1 (D-sub 25-pin or DB-25) socket for the ITU-T G.703 are
provided; the TB1 terminal is provided for the DC power input.

Overview

The O/E and E/O conversion is performed on both transmit and receive signals from the
GRL200 IED respectively. The optical signals are encoded in CMI type (50% duty factor) and
it makes the signals easy to be checked during commissioning. Code conversion is performed
for connection to the ITU-T G.703, which is a synchronous interface and provides a 64 kHz
timing signal, which the GIF200 uses for synchronization†.
†Note: When GIF200 unit has lost clock signals coming from MUX, GIF200 unit can send
signals to MUX using GIF200 internal clock signal. This self-running is only
applicable when GIF200 unit is produced in the ITU-T G.703/contra-directional.
FG
DC24 to 220V
GI fiber optic cable
(50/125 or 62.5/125μm)
C37.94 signal
From/to GRL200 IED
CLK signal
Transmitter in
G.703
‡Note:Either "Co-directional (Code=1)" or "Centralized clock/Contra-directional (Code=2)"
is specified by the selection in GIF200 ordering code.

Connection in C37.94 at ST connectors

As shown in Figure 2.1-1, the type of connector for fiber optic (GI type) cable in C37.94 from/to
the GRL200 IED is ST. Note handling with fiber optic cables not to be damaged by rough
TB1/Power
FG
FG
FG
N
G
P
P
TX
E/O
RX
O/E
ST port
Figure 2.1-1 Block diagram in the GIF200
Table 2.1-1 CLK comparison table in ITU-T G.703
Co-directional
No CLK connection
required with MUX
GIF200 unit
DC5V
CLK†
Ra
Code
RX
conversion
Rb
Ta
Code
TX
conversion
Tb
Centralized clock
CLK to be connected with MUX for generate the TX
- 2 -
6F2S1916 (0.5)
CN1/G703
Twist cable
21
20
G.703 signals
23
22
25
24
From/to MUX
Contra-directional
GIF200