how far the two wire transmission (loop power) maximum distance suitable?
Answer Posted / praful
depending upon the cable size and its resistance we can calculate the max. cable length. e.g. if 1 sq.mm copper cable is used then its resist. is 33ohm/km and operating voltage is 24v then its voltage drop for 1km is 17v.so if instrument operating supply is less than the drop voltage i.e (24-17) then we can use upto 1 km otherwise reduce the length as per opr. voltage.
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