why do we use 4-20 ma current why cant o-20ma
Answer Posted / dean hardage
The use of a current loop is to allow operation of the
intrument over a relatively long distance. The use of 4-20
milliaps make possible the use of a 'live' zero and
provides for an indication of a wire break. It also allows
for loop powered instruments to function. At zero current,
the electronics of a loop powered transmitter would not
work and the sensor would be effectively dead.
Is This Answer Correct ? | 7 Yes | 3 No |
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