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use of AIO for 4...20mA transmitters

Posted: 27 Feb 2019, 23:32
by igor_gomez
Hi,

I'm Igor and I'm pretty new in this world. I have connected a 2-wire 4...20mA transmitter to an analogue input (28,26,24). Nothing was coming out, after lots of research, I have found out that the analogue inputs of the Revpi AIO are passive, therefore the transmitter needs an external supply.
I would like to confirm it, and if so, what possibilities do I have apart from adding an external supply to the + of the transmitter, connecting the - of the transmitter to the + of the AIO (pin 28) and connect the - of the AIO (pin 24) to the ground?
thank you

My references:
https://revolution.kunbus.de/forum/view ... =AIO#p2334
https://revolution.kunbus.de/forum/view ... =AIO#p1992
https://revolution.kunbus.de/forum/view ... =AIO#p3715

Re: use of AIO for 4...20mA transmitters

Posted: 29 Apr 2019, 13:33
by dirk
Dear Igor, here are some examples how you can do it:
https://e2e.ti.com/blogs_/archives/b/pr ... mon-issues#