where using the 0-20ma in feiled instrumentation? why its using?

Answer Posted / george mathews

The answer in my knowledge is that if we use a 0 - 20 ma ,
in instrument then we cant distinguish if it is off/ close
stage or the wiring to the instrument is cut off some where
in the connection . Bcos in both the case we will get an
input as 0 ma. But when we us 4 -20 ma here we can say when
the instrument is close and when its wiring is cut off bcos
only then we can get 0ma and 4ma on different condition.

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