why 4-20 mA signal is preferred over a 0-10V signal
Answer Posted / hari krishna
the signal are transmitted from the field to the
controlroom and vseversa through cables. for long
transmission the cable resistance increases.thus if 0-10v
are transmitted over this long distance,due to the
resistance of cable there will be drop in the voltage and
the signal received at the controlroom will not be
accurate. to overcome this difficulty 4-20ma signal is used
for transmission.
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