5.5 Data Communication Interfaces
Figure 29 Data Communication Interfaces
With RS-485 and RS-4
22 interfaces, if the data rate is 9600 Bd or higher and the cabling
from the transmitter to the host is 600 m (2000 ft) or longer, you must use termination
resistors at both ends of the line.
The WXT530 series transmitters with serial communication interface have built-in
termination options. Plain resistor (R) termination or termination with resistor connected
series with capacitor can be selected with jumpers. By default, no termination is selected. In
RS-422 mode, built-in termination is only between RX- and RX+ lines.
If external line termination is used, resistor range 100 … 180 Ω is suitable for twisted pair
lines. Resistors are connected across RX- to RX+ and across TX- to TX+ (with RS-485 only
one resistor needed).
Chapter 5 – Wiring and Power Management
67
sales@streamlinemeasurement.co.uk
www.streamlinemeasurement.co.uk
To Next Page
Loading...
