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Chapter 2: Physical installation
Figure 4: Expanding the system with an RS-485 signal distributor
1. Keypad
2. I/O box
3. RS-485 distributor
4. See section “RS-485 ports” on page 8
Caution
:
Most signal distributors are unidirectional. This means that the signal only
flows from the input towards the outputs. Consequently it is not possible to connect
several keypads.
See section “RS-485 ports” below to configure the RS-485 port communication settings.
RS-485 ports
There are two RS-485 ports on the rear panel of the recorder. See Figure 5 below for
the serial pin outs.
•
Dome RS-485
:
A and B: Connect pan, tilt, zoom control of PTZ dome cameras. A = +, B = -
C and D: Not used
G: Ground of dome camera
G: Ground of keypad
•
Keyb
: Connect the keypad.
8
TruVision NVR 21 (SP) User Manual