How to protect my sensitive electronics from noise induced by AC power line?
Are the circuits the same as the ones that use the ADS1115 (as per your earlier question)? 



  @Andyaka yes they are the one, alongside other complimentary circuits
  – Jake quin


First, the input protection circuits

Given that your input circuits look like this: -



And the TI data sheet says: -


  These filter resistors produce a voltage drop because of the input
  currents flowing into and out of the ADC. This voltage drop could
  contribute to an additional gain error. Limit the filter resistor
  values to below 1 kΩ.


I would go for something higher than 100 ohm for R62 to R63 - possibly 470 ohm or 680 ohm.

The TI data sheet also tells us that the absolute maximum current into these pins is 10 mA (absolute maximum ratings) and so this allows the real external inputs to be 4.7 volts to 6.8 volts either side of the supply rails used for the device. In other words, with only 100 ohm resistors you get a headroom of only 1 volt and I would want to ensure this was maximized without compromising performance so, 470 ohm or 680 ohm would seem sensible.

Because you have now given yourself this headroom, you can put TVS diodes on those external inputs to dirty digital ground with no risk of attenuating or clipping the signals you wish to monitor. You could use 6 to 10 volt TVS diodes and further protect those inputs. This is something I would consider anyway.

The main question:


  My first idea is to shield it with a Faraday cage, but making my own
  Faraday cage seems to be inelegant, i was thinking to somehow hide it.
  I thought if I place it in one of those small metal control boxes


Yes, they actually do a good job of protecting against electric fields and, if they are made of steel/iron will also do a good job of reducing low frequency magnetic field interference that a non ferrous metal cabinet wouldn't cope with at all well.