Hi,
I need connect an Eurotherm 3208 (RS485) to computer via NI USB-485 converter.
What I tried (Eurotherm 3208 with RS485 and NI 485-USB):
1. Following Eurotherm manual, shorting USB-485 pin4 and pin 8 connecting to HE Rx of 3208; shorting USB-485 pin5 and pin 9 connecting to HF Tx of 3208; attach 220 ohm resistor between HE and HF; connect USB-485 pin 1 to HD Com of Eurotherm 3208, but it does not work. Measurement & Automation Explorer can write (I think to USB-485 only) but cannot read from the controller.
2. Following Eurotherm manual and [NI]: 371253e, shorting USB-485 pin4 and pin 8 connecting to HE Rx of 3208; shorting USB-485 pin5 and pin 9 connecting to HF Tx of 3208; attach 220 ohm resistor between HE and HF; shorting USB-485 pin 2 and pin 3, shorting USB-485 pin 6 and pin 7; connect USB-485 pin 1 to HD Com of Eurotherm 3208, but it does not work. Measurement & Automation Explorer can write (I think to USB-485 only) but cannot read from the controller.
3. So shall I try without the 220ohm resistor?
4. And what are the right settings in Measurement & Automation Explorer? Shall I change the default settings in Measurement & Automation Explorer?
Generally, I need know what the correct connections between 3208 (3 wires) and USB-485 (9 pins) are and how to communicate between 3208 and computer.
Thanks a lot.
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