why are use only 4 to 20ma. signal.

Answer Posted / nagarajan audaiyarpatti

In the fault or open condition we cannot find the 0mA as 0
sothat the 4 mA consider as a zero and 20mA as a span ,in
this condition we can maintain 250mohms in the loop,sothat
we use usually 4 to 20 mA instead of 0 to 20mA in the
transmitter for measuring all the parameter such as
pressure ,temperature ,level,flow.

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