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
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Answer Posted / anup ramteke
Answers 5, 6 & 7 are correct. just want 2 add that why cant
we use 3 mA current as lower value. The reason is that there
are many small noise signals that can be picked up by our
signal wire which has the potential of providing upto 3 mA
current. So to be on the safe side to distinguish between
our proper field signal and the noise pick-ups we use 4 mA
as our lower value
| Is This Answer Correct ? | 6 Yes | 5 No |
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