Three Lobby Control Unit Configuration; Figure 18 Dual Lobby Control Units - Mircom TX3 Series Installation And Operation Manual

The Lobby Control Unit senses whether the line in use. If one of the Lobby
Control Units is in use and the user tries to make a call, the other lobby indicates
that the line is in use.
The RS-485 network connection is optional and is only required if the user
decides to connect a PC configurator on one of the panels to configure and/or
monitor both systems.
NSL
Control
Unit
Line1
Lobby
control
unit 1
1 2 3
4 5 6
7 8 9
* 0 # i
Figure 18. Dual Lobby Control Units
3.4

Three Lobby Control Unit Configuration

Figure 19 shows a configuration with many Lobby Control Units connected to
many phone lines using combined ADC and NSL connection types. Line 1 and
Line 2 connect to NSL Control Units while Line 3 connects to a dedicated phone
line.
Telephone Access System Installation and Operation Manual
Version 3.7
LT-969 Copyright January 2017
T/R
Line1
Lobby
control
unit 2
1 2 3
4 5 6
7 8 9
* 0 # i
RS-485 bus
(optional)
Telephone outlet
Central office line
Line1
Lobby
control
unit 1
OR
1 2 3
4 5 6
7 8 9
* 0 # i
RS-485 bus
(optional)
TX3 System
Line1
Lobby
control
unit 2
1 2 3
4 5 6
7 8 9
* 0 # i
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