AC power Fluctuation Logging .

I need to Log Events of AC line Fluctuations using Arduino Uno , Any Ideas are greatly thankful .

What are you using to measure these "fluctuations", there are many, there are frequency fluctuations, RMS fluctuations, glitches...

Most instruments that measure these can already log them.

That being said, at a minimum you need a real-time clock for time-stamping and SD Card or external EEprom for datalogging.

There are ready made solutions:

There are ready made solutions:
Logomatic v2 Serial SD Datalogger - WIG-10216 - SparkFun Electronics

Or, roll your own: off load serial data recording to dedicated 328P and SD card - Storage - Arduino Forum

I want to log AC line Off time and On time and also voltage level of that line time to time .

Then you need a transformer and circuit to change the AC to proportional-to-RMS DC in addition to what I said before, a real time clock and logging device like SD.

Ok Means I need A transformer to Downgrade ac to dc and then i need to monitor that DC supply and log it with sd card ? so please tell the workout for this , means how the workflow goes .. please thanks for giving your time .

Can you give us an idea of your current skill level? We have actually given you more than enough for a reasonably skilled hobbyist.

I am New to arduino and electronics please give idea considering this.

First, buy a UNO and get the blink sketch to work.

Then come back to us for the next steps.

I hope you don't need to do this for a year or so.

I already got uno and worked with blink sketch.

OK, so now get all the other pieces and start getting them to work one-by one.

To measure the AC line voltage you will need a transformer (that goes from your line voltage to about 5 V), full wave rectifier and a 1 uF or so capacitor. You might also need a voltage divider.

Once all the parts work separately, you can start combining them together.

You will proabably need a DVM before all this is done.

Thanks for replying I have this things with me. Please tell what to do next.

"start getting them to work one-by one"

Which of "these things" do you have? If you had them before, why didn't you tell us?