Broken Charger Detector

With this circuit we can detect when charger wire was broken. This detector will work when the charger wire damage the detector will sounds an alarm warning. So we can know the charger wire is broken.

As long as there is a little current flows from the charger to battery the diodes D1 and D2 will conduct.This forward voltage drop of 1.4 V across the diodes make the Q2 ON.So the transistor Q1 will be OFF.When there is no at all any current flowing (when the wire is broken or there is a loose contact) there will not be any drop across D1&D2 and so Q2 will be OFF.This makes the Q1 ON,the buzzer beeps and the LED glows.


Circuit from : http://www.circuitstoday.com/broken-charger-wire-alarm-circuit