Alarm Input And Output Details - Dahua HCVR5204A Series User Manual

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 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.

3.6.1 Alarm Input and Output Details

Important
Please refer to the specifications for the alarm input and output channel amount.
Do not merely count the alarm input and out channel amount according to the ports
on the rear panel.
Figure 3-1
Figure 3-2
Figure 3-3
Figure 3-4
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