why 4 to 20 ma ,why not 0 to 20 or 3 to 15 or anything
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Answer Posted / smruti senapati
with 0-20 ma you canot distinguish between minimum field
value and connection break.with 2-20 ma ,internal circuits
can distunguish between connection break of minimum
value.normally when the value is minimum the transmitter
will give you 4 ma while in case of connection breakage it
will give 0 ma...
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