Introduction to the SINAUT ST7 system
1.6 LTOP overvoltage protection modules
Station control system
48
System Manual, 07/2009, C79000-G8976-C178-07
Figure 1-14 LTOP2 overvoltage protection module
The LTOP overvoltage protection module is available in two variants:
LTOP 1
Overvoltage protection module for use at the start or end of a 2-wire dedicated line.
LTOP2
Overvoltage protection module for use at the start or end of a 4-wire dedicated line or in a 2-
wire tapping point. In a 4-wire tapping point, two LTOP2 modules are required.
Table 1- 3
Overview of the LTOP modules
Short name
Order no.
Explanation
LTOP1
6NH9821-0BC11
Single line transformer LTOP1, with one OPM
overvoltage protection module for use at the start or
end of a 2-wire dedicated line
LTOP2
6NH9821-0BC12
Double line Transformer LTOP2, with two OPM
overvoltage protection modules for use at the start or
end of a 4-wire dedicated line or a 2-wire tapping
point
OPM
6NH9821-0BB00
OPM overvoltage protection module for LTOP1 and
LTOP2, plug-in (pack of 4)
The two LTOP variants have both screw terminals and an RJ-12 Western jack. The WAN
cable (RJ-12 - RJ-12) supplied with the MD2 and MD3 modems (used as dedicated line
modems) can be connected directly to this RJ-12 jack.
Note
The LTOP modules are not suitable for protecting dial-up connections (telephone and ISDN
network). Companies such as Phoenix and Dehn offer TAE6, S0, RJ-12, and RJ-45 jacks
with overvoltage protection.
1.6.2
Technical specifications of the LTOP overvoltage protection module
LTOP
Transmission paths
Private transmission lines with or without loading coils
Transmission ratio
1 : 1; ± 5 % (e.g. 600/600 ohms in the voice band)
