why do 4 mA serves as 0% not 0 mA?
Answers were Sorted based on User's Feedback
Answer / s.farhan haider rizvi
becouse we can't get 100% sure our device are working
properly or not working.we know that 0 MA DEAD condition
and 4 MA live dead condition,
Is This Answer Correct ? | 20 Yes | 0 No |
Answer / alok kajla
we use 4ma lowest value because it shows that devide is in working condition and at lowst level. if we take 0ma as starting point then we can't differ the situation that device giving lowest value or device is off condition.
Is This Answer Correct ? | 10 Yes | 4 No |
Answer / abhishek rathore
4mamp current signal consider as 0% if sensor or wireing fault then signal goes to 0mamp controller or operator understand signal fault mode goes.1,2,3mA not consider because bydeafault 1-3% signal present in the systembut 4mA not goes to signal bydefault .so we are consider 4-20mA signal
Is This Answer Correct ? | 2 Yes | 0 No |
Answer / ragu.j
All transmitter are working in 1 to 5volts. So, now we
calculate the V=IR. That means Volt equal to
current*Resistance.
for eg :
calculate to(4ma*250ohms)=1000 milli volt or 1volt
and(20ma*250ohms)=5000 millivolts or 5volts.
Is This Answer Correct ? | 2 Yes | 1 No |
Answer / urooj
4mA is the leakage current that flows in the circuit even
when the least voltage is appied ..
Is This Answer Correct ? | 1 Yes | 6 No |
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