WHY WE NOT USE 2-20mA,1-20mA,3-20mA or 10-50mA SIGNAL?
INSTEAD OF 4-20mA.

Answer Posted / ali abideen ,,

Generally in a transistor some amount of voltage is
required for turning it on. This voltage is the cut in
voltage. Up to this voltage the exists a nonlinearity in
its characteristics. Beyond this cut in voltage the char.
of transistor is linear. This nonlinear region lays between
0-4ma, beyond 4ma it linear. This is why 4-20 ma range is
used.

Is This Answer Correct ?    29 Yes 13 No



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