Fiber-Optic Box
Overview
The fiber-optic box (FOBox) is used for connecting the SWT 3000 via fiber-optic cable with a PDH-Multiplexer
or SDH-Multiplexer. For each transmission direction, a separate fiber is necessary. The FOBox contains the
FOM with the electrical/optical conversion, the interface to the multiplexer, and a power supply.
Further details are described in
2.9.4 Connection to a Multiplexer via FO-Box
An adaptor is installed for the conversion from the system connector to the alarm relay, the connectors for the
digital interface (X.21/G703.1/G703.6), and the power supply connector.
[scfoboxo-011211-01.tif, 1, en_US]
Figure 11-2
The Fiber-Optic Box
Interfaces of the FOBox
The interfaces of the FOBox are carried out by an adaptor converting the pinning of the FOM to a 15-pin D-sub
socket according to the following table:
Table 11-2
Pinning of the D-sub Socket X1
D-
sub
X1
DTE
FO Module
Connector
X1
Function X.21
Name X.21
Name G.703.1 Name G703.6 Signal
Direction
Pin
1
Shield
GNDS
Shield
Shield
-
A1, A31, C1,
and C31
2
Transmit (a)
TxD_A
TX-
TX-
OUT
A12
3
Control (a)
C (a)
OUT
A10
4
Receive (a)
RxD_A
RX-
RX-
IN
A13
5
Not connected
11.2
11.2.1
11.2.2
Fiber Optic Module
11.2 Fiber-Optic Box
350
Smart Communication, SWT 3000 Teleprotection, Equipment Manual
C53000-G6040-C605-1, Edition 03.2020