Mircom TX3-CX-1NP - Figure 21 Multiple Lobby Control Units to Multiple Lines

TX3 System
Version 5.4 TX3 Telephone Access System Installation and Operation Manual 43
LT-969 Copyright 2019
Lobby Control Units 1, 2 and 3 can make simultaneous calls as long as a line is
not in use by another Lobby Control Unit. For example, if Lobby Control Unit 1
uses line1, Lobby Control Unit 2 can use Line 2 and Lobby Control Unit 3 can
use line 3.
When Lobby Control Unit 1 is using line 1 and Lobby Control Unit 2 also wants
to use line1, which is busy, then a line busy message displays on Lobby Control
Unit 2.
Figure 21. Multiple Lobby Control Units to Multiple Lines
1 2 3
4 5 6
7 8 9

* 0 # i
1 2 3
4 5 6
7 8 9

* 0 # i
1 2 3
4 5 6
7 8 9

* 0 # i
NSL
Control
Unit
NSL
Control
Unit
Line1
Line2
Line3
Telephone outlet
Central office line
RS-485
bus
RS-485 from
previous unit
RS-485 to
next unit
Lobby
control
unit 1
Lobby
control
unit 2
Lobby
control
unit 3
T/R
T/R
T/R