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Please explain some more. Or you can look at Building Blocks > Electricity Monitoring > Non-invasive current measurement.

I'll explain more

I deal mainly with energy saving and schools

I have systems I use with sensors (Arduino and Raspberry), I want to add current management

Its mainly being to be to able  measure current drawn by lamp (Led Vs others). So what I need is the ability to measure and get the measurement to my Arduino or Raspberry

The voltage is 220

I want to avoid all calibration as described in the link you sent, so if there a ready to use module it will be helpful but I need the minimal setup / cost

There is no ready-to-use module available in the shop that will be suitable for measuring a current as small as that drawn by a single LED lamp.

Our emonTx design, or a similar design implemented with an Arduino, is designed primarily for whole-house use. So it would be eminently suitable for monitoring the energy consumption of the whole school, but not one lamp. For that, you could use the emonTx module (or your own signal-conditioning front end as described in Building Blocks with an Arduino board) to which you could add a serial output, but would need to use a different current transformer to the one in the shop, you would probably need to change a few components to suit; and then you would need to alter a sketch to change the calibration.

I am struggling to understand what you mean by "sensors (Arduino and Raspberry)". To me, the sensor you need is a current transformer, the Arduino or Raspberry are processors that handle the computations. The RPi does not have an analogue input (though add-on boards are available) but the Arduino (on which the emonTx is based) does, so that makes it a natural front-end for converting the CT output into numbers on a serial link that the RPi can handle.

Without knowing the powers/currents involved, I can't recommend specific components.