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Where -48 volt DC use & why?????????

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Where -48 volt DC use & why?????????..

48v Dc is used in the telecommunication circuit.

 Is This Answer Correct ? 57 Yes 6 No

Where -48 volt DC use & why?????????..

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 ? 41 Yes 5 No

Where -48 volt DC use & why?????????..

in -48v dc system positive + is earthed. Negative- is
giving to the equipment.Normally in automobile dc system
negative is earthed.positive is giving to equipment.in
positive grounding system we can avoid corrossion on
terminals.

 Is This Answer Correct ? 15 Yes 3 No

Where -48 volt DC use & why?????????..

it's true that telecommunications equipments operates on the
negative 48 volts DC.

how can we get any voltage while we are grounding the
positive terminal. pls give details.....

 Is This Answer Correct ? 9 Yes 3 No

Where -48 volt DC use & why?????????..

Thanks for repply

But why not using + ve 48 volt????

 Is This Answer Correct ? 10 Yes 8 No

Where -48 volt DC use & why?????????..

what is difference between + 48V and - 48V and how can we we
get individually

 Is This Answer Correct ? 8 Yes 6 No

Where -48 volt DC use & why?????????..

Even if a high supply current comes,the equipment can
compensate due to -ve voltage

 Is This Answer Correct ? 6 Yes 5 No

Where -48 volt DC use & why?????????..

why do we prefer -48 volt instead of -24volt or -12 volt
etc. ??

 Is This Answer Correct ? 5 Yes 4 No

Where -48 volt DC use & why?????????..

first understand what -48 volt means,it means that when we
grounded the nagtive termnal of supply making it to zero
potential means nagative supply, in communacations we use
negative voltage to reduce the noise and hum level.

 Is This Answer Correct ? 4 Yes 5 No

Where -48 volt DC use & why?????????..

WHEN CLOUDS STRIKE THEY PRODUCE -VE CHARGE ,& FOR DISCHARGE THEY NEED THE ZERO POTENTIAL AT EARTH.IN TELECOM WE R GROUNDING THE -VE TERMINAL OF SUPPLY TO MAKE IT ZERO POTENTIAL .IF WE GROUND THE +VE TERMINAL THEN ALL THE EQUIPMENT WILL DAMAGE OR FIRED BECAUSE CLOUD WILL CHOOSE LOW RESISTANCE
+VE CHARGED ANTENAS.THAT IS THE REASON WE USE -48V.

 Is This Answer Correct ? 6 Yes 14 No

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