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7
1, 2, 3, 4.
Alarm input 1 to alarm input 4. It becomes valid in low voltage.
NO C
A group of normal open activation output.
Rx,TX
It is RS232 port to connect to the COM (debug), keyboard port and
transparent port (transfer COM input and output via the network).
A/B
RS485 communication port. They are used to control devices such
as PTZ. Please parallel connect 120
T
Ω
between A/B cables if there
are too many PTZ decoders.
T
1.9.2 Alarm Input Port
Please refer to the following sheet for more information.
z
4-channel alarm input. Normal open or Normal close type.
z
Please parallel connect COM end and GND end of the alarm detector (Provide external
power to the alarm detector).
z
Please parallel connect the Ground of the combo DVR and the ground of the alarm detector.
z
Please connect the NC port of the alarm sensor to the combo DVR alarm input(ALARM)
z
Use the same ground with that of combo DVR if you use external power to the alarm device.
Figure 1-9
1.9.3 Alarm Output Port
z
1-channel relay alarm output (NO contact). Provide external power to external alarm device.
z
To avoid overloading, please read relay parameters sheet in the
User
’
s Manual
carefully.
z
RS485 A/B cable is for the A/B cable of the PTZ decoder.