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high-power load
３ 、
PTZ decoder connections
A. The grounding of the PTZ decoder and DVR must be shared otherwise the common-mode
voltage will lead to the PTZ control failure. The shielded twisted pair is recommended.
B. Avoid the entrance of high voltage. Make the layout reasonably. Take precaution from the
thunder.
C. In the outlying end connect 120
!
resistance paralleled to reduce the inflection and insure the
signal quality.
D. The 485 AB lines of DVR cannot connect 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 DVR alarm output port is constant opening type.
(1) Alarm input (2) Grounding (3) alarm output (4) +12 Voltage
parameter
meaning
ALM IN
Alarm input
ALM OUT(C, NO)
Alarm output interface(constant open type)
GND
Grounding
+12V
+12 Voltages
2.6.1 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 DVR should be shared.
The NC port of the alarm sensor must be connected with the DVR alarm input port.
The grounding of the power supply and the alarm sensor must be shared when used in external power
