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swati kumari - 15th January 2015 (09:47 GMT)
Why dc is given to bts ,why not ac?
sri - 9th January 2015 (06:56 GMT)
the standard lead acid cells or others are of 12vdc. Mulitiples of 12 gives 48V.
manzer aquil - 28th November 2014 (12:57 GMT)
why use -48 volt why not -50volt in BTS
Vasuki soni - 18th October 2014 (07:22 GMT)
Can negative voltages be used in other domains like power systems preferably to protect equipments from lightning and noise as has been identified in above comments..
gyan - 5th August 2014 (16:02 GMT)
It is -48 V D.C cause of the commercial battery stack available. Commercial battery stack is available in -12 V, -24 V or - 48 V. For info, actually any telecom equipment or for that matter any sophosticated equipment runs on a range of supply voltages by using their own inbuilt SMPS and it is very difficult to maintain a constant voltage by the power source.
BIBHUTI BEHERA - 3rd August 2014 (15:22 GMT)
1* In negative voltage due direct current less noise occurs... As a result telecom equipment gives high output..
2* corrosion less on eqiupment
3* It protect the equipmet fom lightning.
Abid Hussain Khan - 1st February 2012 (05:40 GMT)
Thanks to all for clear my confusion about why telecom equipment use -ev voltage but my question is why it is 48vDC (2*24), why not 50vDC (2*25)??
is there any restriction for DC voltage supply?
MRG - 8th February 2011 (11:16 GMT)
(i) Positive voltages cause comparatively more corrosion in metal than negative voltages.
(ii) Negative voltages are safer for human body while doing Telecom activities.
(iii) Lightning may cause positive voltages in the equipment circuitry. In that case, negative voltages (lack of electrons) neutralize positive charges and prevent excessive heat.
(iv) Negative voltage is safer for long telephone line for transmitting power trough it.
Lalit - 19th January 2011 (10:35 GMT)
Basically many reasons bt first is that noise and intrefrence is min at -ve supply voltage and second is that to protect from lightning
vasanth - 2nd January 2011 (07:49 GMT)
why we are using -48v...
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