Serial interfaces
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IRDH275_D00122_02_M_XXEN/10.2016
7.3 Topology RS485 network (IRDH275B)
The optimum topology for the RS485 network is a daisy-chain connection. In
this connection, device 1 is connected to device 2, device 2 to device 3,
device 3 to device n etc. The RS485 network represents a continuous path
without branches.
7.3.1 Correct arrangement
Three examples for correct arrangement:
7.3.2 Wrong arrangement
Three examples for wrong arrangement:
7.3.3 Wiring
A suitable type of cable for the wiring of the RS485 network is:
screened cable, core diameter 0.6 mm
(e.g. J-Y(St)Y 2 x 0.6), screen on one side connected to earth (PE).
Connection to the terminals A and B.
The number of bus nodes is restricted to 32 devices. When more devices are
to be connected, Bender recommends to use an RS485 repeater DI1.