IC Realtime Combo Series: 8 Channel DVR with built-in 10 LCD monitor - Manual (Page 28)

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The alarm output port should not be connected to high power load directly (It shall be less than
1A) to avoid high current which may result in relay damage. Please use the co contactor to
realize the connection between the alarm output port and the load.
3. How to connect PTZ decoder
a. Ensure the decoder has the same grounding with 10.2-inch combo DVR, otherwise you may
not control the PTZ. Shielded twisted wire is recommended and the shielded layer is used to
connect to the grounding.
b. Avoid high voltage. Ensure proper wiring and some thunder protection measures.
c. For too long signal wires, 120Ω should be parallel connected between A, B lines on the far end
to reduce reflection and guarantee the signal quality.
d. “485 A, B” of 10.2-inch combo DVR cannot parallel connect with “485 port” of other device.
e. The voltage between of A,B lines of the decoder should be less than 5v.
4. Please make sure the front-end device has soundly earthed.
Improper grounding may result in chip damage.
3.9.1 Alarm Input and Output Details
You can refer to the following sheet and
X288H288H288H
Figure 3-8 for alarm input and output information.
Figure 3-8
Parameter
Grounding Alarm
Ground line
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
3.9.2 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 10.2-inch combo DVR and the ground of the alarm
detector.
AB Connection
port