Black BLK-HDPTZ12, Руководство пользователя

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3 2MP 12X PTZ HD-SDI/HDcctv Dome Camera
SECTION 1: INTRODUCTION
In the diagram above, video output from each camera on the network is applied to a distribution box (J-box), then connected to a
multiplexer, DVR/VCR, and monitor.
The PTZ features of the cameras are controlled across an RS-485 network with a PTZ controller. Up to 99 BLK-HDPTZ12 cameras can
be attached to a single RS-485 network.
1.2.1 RS-485 network termination
RS-485 networks are usually configured as a series of point-to-point (multidrop) nodes, a line or a bus (star or ring configured
networks are not recommended). Termination resisters are required for devices at the ends of the bus to reduce signal reflections
in the network that can cause data corruption. The value of each termination resistor should be equal to the cable characteristic
impedance, typically 120 ohms for twisted pair cable. In the following illustration of network examples, the grayed devices are
configured to apply termination to the RS-485 bus.