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Help please about the very simple power failure light project


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1. 240V A/C seems a little bit much for this circuit. And a 9V Battery seems like a bit too little to power 3 LED bulbs...What would be the implications of powering the circuit from 110V AC outlet?

2. The author of the project didn't seem to define all of the components on the schematic. For a newbie like me that makes this a very difficult project. Any ideas on what components J1-J5 might be?


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1) The voltage means nothing. It's possible to design a huge electric car which runs off 48V or a little wall clock which runs off 240VAC. Voltage alone equal power, look up Ohm's law.

It's a silly idea, D1 to D5, R1 and C1 should all be removed and a 240VAC relay used.

A 9V battery can easily power three LEDs like this, although they must be red, orange, yellow or green which have a low voltage drop about 1.8V to 2.2V. Blue, white and violet LEDs have a higher voltage drop of 3.5V so should each have their own resistor.

2) J just means jumper or plug which can connect to another circuit which is explained by the text.

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