Camera Supply; Figure 10 Rs-485 Connections - Mircom TX3 Series Installation And Operation Manual

2.6.6

Camera Supply

The camera supply connection provides + 12 VDC, 600 mA. The camera is
controlled by one of the general outputs. The camera's positive terminal connects
to the normally open (NO) general output relay contact. The common (C) contact
of the general output relay connects to the + 12 VDC supply terminal. The camera
is typically configured to operate when the main door is open.
2.7 RS-485
Note:
Maximum length: 4000 ft (1219.2 m)
22 AWG twisted pair, or Cat 5 cable
The RS-485 terminals are located at the bottom of the board. An RS-485 terminal
lets you easily connect multiple Emergency Phones, card access units, and lobby
control units across a network. The RS-485 connection consists of two separate
terminals, one for input and one for output. See Figure 10.
Panel 1
First panel on network
Figure 10. RS-485 Connections
TX3 Emergency Phone Installation and Operation Manual
22
LT-6113 Copyright 2017
If you do not have end-of-line 120 Ω resistors, close JW5 on the first
and last panels instead. See section 2.4.4.
120 Ω
Optional common
reference connection
if available
Panel 2
Connect shield to chassis
ground on one panel only
Installation
Panel 3
Last panel on network
120 Ω
Version 2