Why we use 4 to 20 mA, (This is International Standard)
instaed of this can we use 4-16, or 4-24 or 3- 15 or any
other range
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Answer Posted / nilesh upadhyay
There are basically 2 reasons of using 4-20ma
1. we can know whether the instrument is working properly
or not. we can distinguish "live zero" and "dead band". if
there is problem in instrument then also it is going to
show zero and if there is no supply then also it will show
zero so we can differentiate this two.
2. 4-20ma is linear with 3-15psi .
Nilesh Upadhyay...
| Is This Answer Correct ? | 23 Yes | 12 No |
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