Hello,
why is 4- 20 mA a preferred range of current in instrumentation?
The following are the reasons
1.Easy to identify the broken wire , rather than using 0- 20mA
2.Noise immunity ,the current range from 4-20mA, is free from electromagnetic interference , then the signal are safe through the area of travel
3.4-20 mA current signal is safe for hazardous area because of low power, and there is no risk of electric shock or fire.
4.Current does not drop with length of the conductor , as it happens in voltage