why using 4-20ma not using 0-20or why not using 1-
20ma???????

Answer Posted / rathod mukesh

0 - 20 ma range is not use in the instrumentaion as standard range because if we use 0 ma for zero process parameter value, if any reason loop wire become break although plc or micro controller get 0 Value at unkown process parameter value and its understand process is in healthy condition but actcully fault is occur in physical data(0-20 ma) transmission link . the plc or micro controller is not accept proper value of process prameter. And we cant define live zero of process parameter. Use to 4- 20 rane ma we easily define live zero.

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