SiboTech ENB-302MT, Руководство пользователя

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as follows:
1. The basic characteristics of RS-485 transmission technology
①
Network topology: Linear bus, there are active bus termination resistors at both sides.
②
Transfer rate: 300 bps~115.2Kbps.
③
Media: Shielded twisted-pair cable and also can cancel the shielding, depending on environmental
conditions (EMC).
④
Site number: 32 stations per subsection (without repeater), and can up to 127 stations (with RS485
repeater).
⑤
Plug connection: 3-pin pluggable terminal.
2. The main points on RS-485 transmission equipments installation
①
All the equipments be connected with RS-485 bus;
②
Subsection can be connected up to 32 sites;
③
The farthest end of each bus has a termination resistor—120Ω 1/2W to ensure reliable operation of the
network.
B+
A-
GND
1
2
3
485+
485-
RS485 device
RS485 interface of
ENB-302MT
RS485 device
RS485 device
485+
485-
485+
485-
…