Fig 4. Example connection to RS485 2-wire network
3.3.1. GND TERMINAL CONNECTION
Connection of GND terminals of RS485/422 interfaces, devices connected to RS485/422 bus, should be done in the case of a
potential difference of the signals grounds on interfaces RS485 / RS422, which prevents proper data transmission.
Cannot connect to the GND terminal - cables screens, PE circuit of electrical installation, signals grounds of other devices.
3.3.2. LINE TERMINATION
Using Line Termination (terminator) Rt = 120
W
will reduce electrical reflection in data line at high baud rate. It is not needed below
9600Bd. Should be used Line Termination resistor if the distance is over 1000m @ 9600Bd or 700m @ 19200Bd transmission.
Example connection of Rt (connected to screw terminal block of RS485/422 interface) are shown on Fig. 3 & 4.
3.4. CONNECTION TO 1-WIRE NETWORK
3.4.1. CONNECTION TEMPERATURE SENSORS
Connections of 1-wire temperature sensors to ADA-401WP module are shown below.
Fig 5. Sensor connection to ADA-401WP module with (3-wire) 1-WIRE network
7
ADA-401WP
(5) GND
GND
(2) Rx
(3) Tx
ADA-I1040
GND (5)
Tx (2)
Rx (3)
Rt
Rx+
Rx-
Tx+/ A
Tx-/ B
ADA-401WP
RS485(2W) Bus
ADA-401WP
ADA-401WP
RS232
Connector
RS485/RS422
Connector
RS232
Connector
PC
V+
1-WIRE
Connector
RS485/RS422
Connector
1-WIRE (3W) Bus
ADA-401WP
VDD
GND
1-W
Rx+
10–30VDC
3W
Tx+/ A
Tx-/ B
GND
Rx-
Power Supply
Vss-
Vss+
V-
DS18B20 Sensor
DS18B20 Sensor
DS18B20 Sensor
