User manual

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C. In the outlying end connect 120Ω resistance paralleled to reduce the inflection and insure the
signal quality.
D. The 485 AB lines of NVR can not connected with other 485 output equipments paralleled.
E. The voltage between the AB lines of the decoder must be less than 5V.
4、Front equipment grounding note
Bad grounding can lead to the burnout of the chip.
5、Alarm input type unlimited
The NVR alarm output port is constant opening type.
1 2 3 4
(1) alarm input (2) grounding (3) alarm output (4) RS485
parameter meaning
SENSOR
Alarm input (1、2、3、4)
GND grounding
COM1、NO1 Alarm output interface(constant open type)
+、-
485communication interface which is connected with the
recording control equipments such as the decoder
2.4.1 Alarm input port specification
1 channels alarm input. Alarm input type unlimited.
The grounding and the com port of the alarm sensor are parallel (The alarm sensor is external power
supply) .
The grounding of the alarm and the NVR should be shared.
The NC port of the alarm sensor must be connected with the NVR alarm input port.