Avtronix AD-808Q, Руководство пользователя, Страница: 11 / 41

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RS485
RS485 A/B cable is for the A/B cable of the PTZ decoder. When the DVR receives a camera
control command, it transmits that command up the coaxial cable to the PTZ device. RS485 is a
single direction protocol; the PTZ device can’t return any data to the unit. To enable the operation,
connect the PTZ device to the RS485 (A,B) input on the DVR.
Since RS485 is disabled by default for each camera, you must enable the PTZ settings first. This
series DVRs support multiple protocols such as Pelco–D, Pelco–P.
To connect PTZ devices to the DVR
Connect RS485 A,B on the DVR rear panel.
Connect the other end of the cable to the proper pins in the connector on the camera.
Please follow the instructions of PTZ device for camera configurations.
To connect PTZ Decoder
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.
Avoid high voltage. Ensure proper wiring and some thunder protection measures.
For too long signal wires, 120 Ω should be parallel connected between A, B lines on the far end to
reduce reflection and guarantee the signal quality.
“485 A, B” of DVR cannot parallel connect with “485 port” of other device.
The voltage between of A,B lines of the decoder should be less than 5v.