Rs 485 Serial Port - Vetek DGT Technical Manual

DGT / DGT60 / DGTQ / DGTP

11.8 RS 485 SERIAL PORT

On the same RS 485 line it's possibile to connect up to 32 indicators.
Figure 1: electrical diagram of the connections and the 2 termination resistances.
On the RS485 network normally one connects 2 termination resistances of 120 ohm (shown with "R" in figure 1),
ONLY on the 2 devices which are at the 2 ends of the cable.
The maximum reachable length from the line with the use of the appropriate cable for RS 485 connections, the
twisted 2x24 AWG duplex cable, shielded with external sheathing + aluminium band, is of about 1200 meters.
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