Why we use 4 to 20 mA, (This is International Standard)
instaed of this can we use 4-16, or 4-24 or 3- 15 or any
other range

Answer Posted / rajesh.a

STANDARD VOLTAGE IS 1-5V DC,250OHM RESISTANCE

AT V=I*R
AT 1V=I*250OHM = 4MA
AT 5V=I*250 OHM = 20MA

SIMPLE CALCULATION

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