What is the differance between negative dc voltage and
positive dc voltage because some circuit uses -24,-5,-12,-
15,volt dc supply

Answer Posted / alok gangwar

A negative line voltage helps to reduce the corrosion from
electrochemical reactions occurring on a wet telephone
line. Also -48v DC is more stable than +48 volit, so -48 V
is preferred.

Is This Answer Correct ?    32 Yes 7 No



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