Consultation on signal isolator usage
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As shown, it is now powered by a PLC, and it is a two-wire transmitter. I want to achieve an analog output with no voltage at terminal 5.6. May I ask if the PLC wires are connected to 1.2, and 3.4 is directly connected to the transmitter? Or connect the PLC wires to 3.4, and run a wire from 3.4 to the transmitter. Or rather, 1.2 is connected to the external power supply, the PLC is connected to 3.4, and 3.4 is then connected to the transmitter?
For this signal distributor, connect the PLC inputs to 5, 6, or 7, 8; there should be a DIP switch on it for setting active or passive mode
The wiring for different models from various manufacturers varies. Just find the manual based on the model, and you’ll know how to connect it.
Please refer to the user manual of the isolator you are using; different manufacturers use different wiring methods. It’s not possible to connect the PLC to terminals 34 and then have those terminals connected to the transmitter, as you suggested. Generally, there are separate terminals used for this purpose – but how can signal isolation still be achieved in that case?
One and two: 5, 6, and 78 are passive components; 1 and 2 are connected to the power supply, which should be DC 24V. 3 and 4 are connected to the field primary meters, and there should be a voltage of DC 24V there as well