A
Asad
>Why 4-20 ma is used in Analog Signals?
>How come ISA selected this. Why not
>5-21ma?
During an Internal training at our company this topic came up. One answer which I liked was 4-20 ma gives 16 ma range which can easily be translated to 4 bit and if we take 0.5ma step then giving 32 levels which can be dealt by 5 bits and so on. I don't know if this was the reason but if not its a good coincidence. Easy Analogue to digital conversion.
>How come ISA selected this. Why not
>5-21ma?
During an Internal training at our company this topic came up. One answer which I liked was 4-20 ma gives 16 ma range which can easily be translated to 4 bit and if we take 0.5ma step then giving 32 levels which can be dealt by 5 bits and so on. I don't know if this was the reason but if not its a good coincidence. Easy Analogue to digital conversion.