why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything
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Answer Posted / sukhiray
the lowest value is not 0 to create a difference in between
broken ckt or any other error in ckt and actual min current
value.
b'coz for broken ckt or any other fault in ckt the current
o/p will be 0. means no current. but when it is 4 , then it
is the min o/p of the ckt and the ckt is running properly
both is confirmed.
the upper limit is a conventional one, no such reason behind
it. but it is a value practically can be achieved by the
designer easily.
4-20 ma could be taken it is followed by all manufacturers.
| Is This Answer Correct ? | 94 Yes | 18 No |
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