Re:Never trust a system that seems to be working
by invalidator on Monday October 17, 2022 @05:46PM
(#33239936)
That's one reason, but the big one is that it makes it easy to remote-power the sensors. It gives them a 4mA budget to Do Their Thing even when outputting a zero.
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Re:Never trust a system that seems to be working
by weaksauce on Monday October 17, 2022 @10:31PM
(#33242299)
I would say the independence of conductor length to voltage drop since current is measurable at any point in the wire is more important. another big advantage to it is that it also is resistant to noise. (though you should be using grounded on on end TSP anyway) nowadays it's pretty common to use cat5 and read a bunch of things from the sensors though via various protocols. 4-20mA sure is a lot simpler to program against though.