Why we are using 4-20 mA as Analog signal transmission
other than 3 to 19 or 2 to 18 or 6 to 22 like wise ? What
is the reason behind using 4 & 20 mA? Can anyone give
proper technical reply ?
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Answer Posted / abhishek
this 3-15 psi later used in electronic signal as 4-20mA. 4mA
used as live Zero , & 20mA is current so
20mA*24V=480mWatt. this power if we increase any signal
wire can cause such type of arc that can cause Fire.
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