Vitek VT-PTZ12WH, Руководство пользователя

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VT-PTZ12WH
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2.6 Principle of Termination
There are two general types of wiring scheme for PTZ cameras:
•
Daisy-Chain Wiring
•
Home-Run Wiring
Each scheme has a different termination method
Daisy - Chain Wiring
Every device that is connected at the end of the communication data line (daisy-chain)
must be terminated by either the DIP switch setting or an appropriate device such as a
termination jumper to prevent potential control signal errors. Usually this means only the
last camera in the chain is terminated.
Home - Run Wiring
Home-run wiring forms a star shape. Each camera connects to one central location on
the star. That central location is usually the junction-box of a keyboard or may also be
the RS-485 input to a DVR. With home-run wiring, none of the cameras should be
terminated.
See Figure 6 for termination switch settings and Figure 7 for examples of devices
requiring termination. Note: Total length of the cable for communication should not
exceed 1.2Km or .74 mile.
** Unless communication error, put the position 2, 3 of the S5 in OFF state.
Position 2, 3 should be set as a pair. (Both 2, 3 to ON position or OFF position)
S5 D1 D2 D3 D4
Terminated
Not
Used
X X ON
Not terminated X X OFF
Pull Up/Down ** ON ON X
Normal ** OFF OFF X