Emerson Dixell XWEB300, Operation Manual, Page: 13 / 114

1592028000 XWEB300D_500_500D opr GB r2.2.0 2013.08.01.docx XWEB500/300 13/114
2.1.2 SERIAL ADDRESS

The cable must have 2 or 3 wires with shield, minimum section 0,5mm
2
(e.g. the BELDEN 8772).
 From the XWEB position the cable reaches all the instrument positions.

Do not execute loops or derivations:
Right connection
Wrong connection

Do not connect shield to ground.

Do not connect the “ Gnd ” terminal.
 Remember to draw a map of the line. This will help you to find an error if something is wrong.
 The instrument with RS485 have “ + ” and “
-
“ terminals, respect the polarity.

To keep the line balanced it is necessary a 120 Ohm resistor at the end of the line (you can use the RS
485+ and RS 485- terminals of the last instrument connected).
2.1.3 THE TTL OUTPUT