Techpro TRIDVR-EL8C, User Manual

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3.6 Alarm Input and Output Connection
Please read the followings before connecting.
1. Alarm input
a. Please make sure alarm input mode is grounding alarm input.
b. Grounding signal is needed for alarm input.
c. Alarm input needs the low level voltage signal.
d. Alarm input mode can be either NC (normal Open) or NO (Normal Close)
e. When you are connecting two DVRs or you are connecting one DVR and one other
device, please use a relay to separate them,
2. Alarm output
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 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 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.