Using ADA-4020 converters it is possible to create Current Loop bus as above.
In above example the current loop bus creates on converter ADA-4020-1-1-2-2-3 (MASTER –
Active Transmitter
), one converter
ADA-4020-1-1-2-2-3 (SLAVE -
Active Transmitter
) furthest from the converter MASTER and max. 14 converters ADA-4020-1-1-2-2-3
(SLAVE –
Passive Transmitter
). The number of SLAVE converters can be less for long lines.
3.6. POWER SUPPLY CONNECTION
The power supply to the ADA-4020 converter should be DC (regulated) from 10 V= to 30V=. Nominal power is typically 2W, e.g. ZS-
12/250, DR-15-24. Power cable from DC power supplies to device must not be longer than 3m.
Observe the polarity, connect positive (+) of DC power supplies to V+ and negative (-) end to V- terminal. ADA-4020 has the protection
from opposite connection power supply. If after connection power supply on the front panel of the converter not light green LED PWR,
check correctness of power connection (polarization).
4. CONFIGURATION
The operating mode of ADA-4020 converter is set by the use of 6-positions SW1 switch.
This switch is located near the screw terminal block (see Fig.1). To set the SW1 should be removed a terminal cover and using small,
flat screwdriver make correct setting.
4.1. OPERATING MODE SETTING
All available operating modes are shows in table below.
If there are any additional questions, please contact with technical support: suppor@cel-mar.pl or on the phone: +48 41 362-12-46.
Table 1.
SW1-1 SW1-2 SW1-3 SW1-4 SW1-5 SW1-6
Description
Operating mode
OFF
OFF
OFF
OFF
OFF
OFF
RS-422 network
4-wire RS422 network.
Full duplex or half duplex
transmission.
ON
ON
ON
ON
ON
ON
RS-485 network, automatic data flow
control
2-wire and 4-wire RS485 network.
Full duplex or half duplex
transmission.
4.2. FACTORY DEFAULT
During production ADA-4020 converter is configured to operating in RS485 mode as in table below.
Table 2.
SW1-1 SW1-2 SW1-3 SW1-4 SW1-5
SW1-6
ON
ON
ON
ON
ON
ON
5. ACTIVATION
Converter can be powered after proper connection according to steps above. If the connection was made properly green LED PWR on
front panel of converter should lit, if not check polarization of power connection. If the red LED RX is lit check correctness of
connection transmitting line of Current Loop Device. The lighting of RX LED indicates no current flow through the optocoupler in the
receiver's circuit.
During proper data transmission through converter the LEDs Tx and Rx should blink.
LED
Description
PWR
Signalization of Power Supply
RX
Signalization of data receiving by ADA-4020 from Current Loop.
TX
Signalization of data transmission from ADA-4020 converter through Current Loop
10
ADA-4020
