what is the current flow from telephone when call is made?
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Answer / sparkindia
when telephone is in on hook condition (in idle
condition):voltage:-48v(minus voltage is used only for
protection purpose)
current: less than 5 micro Amp (idle
0 amp)
when telephone is in off hook condition (in use condition):
voltage:Between- 9V to- 3V
current: 20 mA to 30 mA
Resistance of telephone circuit (like our bsnl telephone)
is 200ohms.But it can vary as per manufacturer.
When telephone is ringing:Ringer voltage:90V AC
90V AC Ringer voltage is superimposed on 48V DC.
above data is calculated for telephone lines having
distance of almost 4.5 km between home and telephone
exchange which is generally used.
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