Answer Posted / ibrahim s

4-20mA :-
* Easy to find the open circuit(because this
signal level starts from 4mA, if the circuit in open the
output shows 0mA, so we can find easily the open circuit).

* Easy 0 to 100% segregation
4mA - 0%
8mA - 25% 12mA - 50%
16mA - 75% 20mA - 100%

* All manufacturer following the same standard.

0-20mA :-
* If it starts form 0mA, not able to find open
circuit easily.

3-15mA :-
* Less linearity, because 3mA is 0%, 15mA is 100%
so the deviation b/w 3-15mA is lesser than 4-20mA, So that
it reduces the accuracy of the measurement.



So that 4-20mA is preferred over 0-10v

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