plcnoob (Customer) asked a question.
How do I record/monitor retransmitted PV data from a Prosense Process Controller?
We use the controllers for our lab furnaces. I'd like to use the retransmit functionality to record the temperature data.
What type of PLC module would be required to receive the signal from terminals 205 and 206? I'd like the setup to be as simple as possible (avoid adding resistors individually since we have hundreds of controllers).
Most of the analog PLC modules I've looked at require and external 24 VDC power source. Is that needed with the retransmitted data since the controllers can either retransmit or use those terminals as a 15V power source?
Simple wiring, or simple programming?
How many is "hundreds"?
How fast do you need to log the data?
What is the part number (or series at least) of your process controllers?
Analog signals from hundreds of controllers will mean lots of wiring and expensive hardware, but the data collection can be relatively fast.
RS-485 cabling with Modbus programming will mean lots of programming and need a PLC with multiple RS-485 ports or multiple PLCs. The wiring will be much simpler and the update rate will be slower than analog hardwiring.
In either case, depending on how these controllers are physically laid out, having multiple data collection PLCs and a central SCADA or HMI data concentrators will probably be a worthy consideration.
Another option would be to use a gateway module like this:
https://www.automationdirect.com/adc/shopping/catalog/communications/serial/modbus_gateway/sgw-mb1524-t
We have Yokogawa ut35a and Prosense PPC5-1000 controllers. The vast majority are the base models without RS-485 or ethernet and so I'm investigating what it would take to record/monitor the retransmit functionality of these base units.
We are currently monitoring thermocouples on a Yokogawa GM10 setup which is 1 reading per second and we are recording every 5 or 10 seconds.
It seems like I need aPLC unit with analog input modules with isolated inputs that can accept the powered 4-20ma retransmit signal.
+1 OkiePC
The following post will show you Modbus RTU communication (RS485) back to a computer running AdvancedHMI. A Solo temperature controller is used in the post, but you will get the idea.
https://accautomation.ca/advancedhmi-to-solo-process-temperature-controller/
I hope this helps you out.
Regards,
Garry