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Maximum current that can be drawn?

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ajaykumar988

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Anyone has an idea how much current can be drawn from a phone line ?
I think here in Canada they're 48VDC lines, but I have no idea how many
mAs can be pulled without breaking something / getting noticed...
 

it will be nearly 200mA it is not possible to draw much current
If anyone draws more than specified current, telephone control will think there is problem in line then line will be disconnected for protection
 
The simple things are that the telephone line is a balanced transmission line which can have up to 120 ma of DC current from up to 56 VDC (actually in some cases up to 90 VDC) and up to 120 VAC RMS (ring voltage) in the way of various voltages and currents. Those voltages and currents can be any polarity and might be applied all at one time.
Click to expand...

Quoted from:
**broken link removed**
where you can find some more details ..

Regards,
IanP
 

That is the theoretical values only. How much you can draw still depends on your operator's policy, for example, maybe you can use up to 50mA, but maybe with 50ma you will be complaint - they worry about the dropped out voltage from the whole network.

nguyennam
 

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