Dahua Technology DH-XVR71 H-4K-I2 Series, User Manual

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User’s Manual
41
Icon Description
NO1 C1, NO2 C2,
NO3 C3
There are four groups of normally open activation output (on/off button).
Ground cable.
485 A/B
485 communication port. They are used to control devices such as decoder.
120 Ω should be parallel connected between A, B lines if there are too many
PTZ decoders.
4.3.2 Alarm Input
Refer to the following figure for more information.

Grounding alarm inputs which includes NO (Normally Open) and NC (Normally Closed) type.

Parallel connect COM end and GND end of the alarm detector (Provide external power to the
alarm detector).

Parallel connect the Ground of the DVR and the ground of the alarm detector.

Connect the NC port of the alarm sensor to the DVR alarm input (ALARM).

Use the same ground with that of DVR if you use external power to the alarm device.
Alarm input
4.3.3 Alarm Output

Provide external power to external alarm device.

To avoid overloading, read the following relay parameters table carefully.

RS-485 A/B cable is for the A/B cable of the PTZ decoder.
4.3.4 Alarm Output Relay Parameters
Refer to the actual product for relay model information.
Table 4-2 Alarm output relay parameters