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Foxboro 761 - Output Clamp?
Is it possible to configure output limits (clamps) on a Foxboro 761 Series Single Station Micro Plus Controller?

Can output limits (clamps) be configured on a Foxboro 761 Series Single Station Micro Plus Controller?

We have one of these old controllers still in service on a live plant. A requirement to limit its control output signal has come about. Documentation is sketchy and I don't have a spare to play with. Can it be configured to keep its output within a certain range, rather than the full 0-100% (4..20mA) range?

The 761 spec sheet says it has a characterizer.

The 762 characterizer can characterize the output signal, according to the blurb in the 762 manual:
https://s1.postimg.org/kt4q22mvj/Foxboro_762_characterizer.jpg

Do a 3 point characterization, say, limit the output to 85% max:
The 'input' (below) is the control output signal (input to the characterizer).
The 'output' (below) is resulting characterized signal:


input output
0 0
85 85
100 85