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

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Question Posted / shri..

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Ericsson, INDUS, Indus Towers, Telecom, I also Faced
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Where -48 volt DC use & why?????????..

Answer / pundlik wanwe

48v Dc is used in the telecommunication circuit.

Is This Answer Correct ?

57 Yes

6 No

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

Answer / rabi

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?????????..

Answer / subra

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?????????..

Answer / anant gupta

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

4 No

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

Answer / shri..

Thanks for repply

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

Is This Answer Correct ?

10 Yes

8 No

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

Answer / muralichppl

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

Is This Answer Correct ?

8 Yes

7 No

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

Answer / avinash

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?????????..

Answer / maxiquiet

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?????????..

Answer / jitender kotwal

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?????????..

Answer / hemant

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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