I am trying to create an electric meter reading setup for Arduino, and I have been searching for it and almost every posts available is using LDR sensor.
http://www.reuk.co.uk/wordpress/solar/flashing-led-on-electricity-meter/
And since it is using LDR, the system should be kept in a dark area, or that the LDR is taped to the flashing LED so that no other light source will interfere the sensor.
But I wanted to have a different setup, and what I am thinking is:
1.) inside the electric meter, tap into the blinking LED
2.) From the LED, connect it to an LLC (https://www.sparkfun.com/products/12009)
3.) From the LLC, connect it to the Arduino
4.) Arduino will sense/detect the pulse of the LED.
Is this a possible setup? Will it not fry the Arduino or the LLC? Will Arduino be able to detect the pulse?
If not, are there any other options? can I use discrete components instead? (I will be the one creating the circuit connection for the LED and Arduino, using resistor, diodes, etc.)
1.) inside the electric meter, tap into the blinking LED
Nope. The reason everyone uses an LDR is that the electricity company will not take kindly to you messing with their meter, by which I mean that they will likely set their lawyers on you when they find out.
Take a look at your meter - you will likely have some kind of stamped seal that you would need to break to get into the box. You really really don't want to disturb that seal.
There was a thread a few days ago about someone who had a meter that has a component you can get from the manufacturer that generates pulses via hall sensor IIRC. You might look to see whether your meter offers such a feature.
In general though, it's easiest to follow the crowd and use an LDR.
I am quite aware that tamepering/modifying the electric meter is illegal. But I am only doing this for a project 
Hi,
How do you know that the circuit in the meter will give you the signal you require, the circuitry does not have to be referenced to gnd like your measuring circuit will.
I cannot think of a project that needs to do this, unless it is for a meter manufacturing company, in which case you would not be enquiring here on how to do it.
What is the application?
Tom...