why use -48 volt DC power in telecom?

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why use -48 volt DC power in telecom?..

Answer / prasanna kumar das

To prevent the equipments from lightning strokes. Because
the cloud is negatively charged at bottom it requires a zero
or a positive potential to discharge, and it selects the
ground (Zero potential) to discharge. If the Telecom
Equipments are fed with positive the cloud will choose the
low resistance tallest positively charged Antenna's to
discharge, this could damage the entire setup of Telecom
equipments. So the Telecom equipments are fed with Negative
supply Voltage

Read more:
http://wiki.answers.com/Q/Why_telecom_equipments_work_in_negative_voltage#ixzz23mgK9os7

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why use -48 volt DC power in telecom?..

Answer / ashish bansal

if got, Kindly mail me to

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why use -48 volt DC power in telecom?..

Answer / mukesh

i dont no. so please give me perfect answer on my email.

urgent.

thanks.

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