When a field input to plc is coming from 400 to 600 meters
and the input is in 24 V DC? So signal cable of which cross
section i should select for proper signal to plc?

Answer Posted / janes

It is all depends on the Load of the Field Instrument.
After Getting the load apply the Voltahe Drop Formula.
Also the input is 24VDC but define the Amp. is it 20A/ 10A.
that is 24Vdc 10A.

For 24VDC 10A Power supply and the Field Instrument is SOV
with 18 Watts, and the Distance is 600 meter then use the 2
Core 2.5 Sqmm Cable as per below Formula.

% Voltage Drop = Length X Current X R Cos0 + X sign0 /
Number of run X Voltage X 10.

Is This Answer Correct ?    2 Yes 5 No



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