LAUMAS LCB, Руководство по установке

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RS485 SERIAL COMMUNICATION
If the RS485 network exceeds 100 metres in length or baud-rate over 9600 are
used, two terminating resistors are needed at the ends of the network. Two
120 ohm resistors must be connected between the “+” and “–” terminals of the
line, on the terminal strip of the furthest instruments . Should there be different
instruments or converters, refer to the specific manuals to determine whether it is
necessary to connect the above-mentioned resistors.
DIRECT CONNECTION BETWEEN RS485 AND RS232 WITHOUT CONVERTER
Since a two-wire RS485 output may be used directly on the RS-232 input of a PC or remote display,
it is possible to implement instrument connection to an RS-232 port in the following manner:
INSTRUMENT RS232
RS485 – → RXD
RS485 + → GND
This type of connection allows A SINGLE instrument to be used in a ONE WAY
mode.
INSTRUMENT
RS485 +
RS485 -
max 500 m
RS485 +
3 2 5
PC R
S232
RX+
RX-
TX-
TX+
CONVLAU
24 VDC
+
-
0
TX
RX
VIN
RS485 +
RS485 -
RS48
5 -
RS485 +
RS48
5 -
RS485 +
RS48
5 -
GND GND GND
INSTRUMENT INSTRUMENT