why use 4-20mA in the field of instrumentation?

Answer Posted / vijay ranipa

if we use 0 to 20ma insted of 4 to 20 ma then we can not
find actual position zero reference output, for example if
we have a motorized valve, it's full close at that time we
get 0ma (0%)reference and at fully open position we get
20ma(100%)reference, in this condition if power supply of is
off then we also get 0ma reference,so here in this kind of
condition we can't get actual result like that gate is
actually close or any other problems as per explanation of
above..

Is This Answer Correct ?    32 Yes 8 No



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