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vdd70
Aug 3, 2008, 04:13 AM
Can I know the DC voltage of Landline In India?

Credendovidis
Aug 3, 2008, 05:02 AM
Can I know the DC voltage of Landline In India?
Here is a link to a website on electric power distribution in India. Note : all electric distribution around the world is done in Alternative Current (AC), and not in Direct Current (DC) - except in some very few special applications.

Electricity in India - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Electricity_in_India)

For more specialized details : see at the bottom of the Wikipedia page the link box to various sub-categories :
Categories | Energy in India | Electricity sector by country | National electric power policy

:)

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KISS
Aug 3, 2008, 07:31 AM
C:

This is in the phone section and your talking about AC power.

Not sure about India or any other country, but in the US on hook is about 48V DC, Off hook about 5 VDC (Really current based) and ringing about 70 VAC at about 20 Hz.

In party line systems, the frequency determines whose phone rings.

EDIT: Fixed the OFF hook

Stratmando
Aug 3, 2008, 07:57 AM
{ believe KISS meant to say 5 volts "OFF HOOK".
I thought ringing was about 90 volts AC/20Hz?

KISS
Aug 3, 2008, 09:27 AM
Strat:

It's 45 to 90 V RMS with 45 volts being the minimum, so I picked something somewhat in the middle of the range.

Stratmando
Aug 3, 2008, 09:59 AM
I found where it can go as high as 140 volts, plus other good info:
http://telecom.tbi.net/phone.htm

KISS
Aug 3, 2008, 10:31 AM
Here is from a design perspective:

http://www.beta-dyne.com/pdf/rg3000_an02_rev03.pdf

Loved the link.