ICC DNET-100, Руководство пользователя

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5. RS-485 Electrical Interface
In order to ensure appropriate network conditions (signal voltage levels, etc.),
some knowledge of the gateway’s RS-485 network interface circuitry is
required. Refer to Figure 7 for a simplified network schematic of the secondary
RS-485 interface circuitry. Note that the “Shield” terminal has no internal
connection: its purpose is simply to provide a cable shield chaining location
between devices. The shield is then typically connected to ground at one
location only.
Figure 7: RS-485 Interface Circuitry Schematic
Figure 8 details the specific network connections to the RS-485 terminal block.
A
B
Signal Ground
Shield
Figure 8: RS-485 Terminal Block Connections