Electrolytic residues

[Jari]

Hello everyone, I am new to this site and I venture into a field
that is not my "daily bread". However, I will see that I am understandable to others:

I have a plastic tub (pp+caco3) full of water and inside this tub is inserted a "electrode" i.e. a circuit that must "understand" the water level of the tub.
the question is this: Why is the circuit covered with a white patina?
All this has to do with electrolytic processes?
if you, how to avoid (see the circuit after not "law" anymore).

thanks for the attention.

 

[zeigs]

Can it be limestone? if it is a white patina is easy. especially if the "electrode" warms up

It may be an electrolytic phenomenon. in boilers to avoid this a bar of sacrificial material is inserted, I think more electronegative than the boiler material itself

 

[Jari]

thanks zeigs, it can be a road that of the "sacrifiable" bar.

But I must rectify that the copper of the circuit is not in contact with water but is packed in a mylar and the reading action level is done by magnetic field (repeto, I am in a matter that is not my friend).
However, when this residue is created (which could also come from the plastic material of the tub) the reader is unavailable.

 

[zeigs]

that I know mylar is a plastic material, so I would exclude the electrolytic phenomenon.
I also do not see how a plastic storage of the tub could affect the magnetic field generated by the sensor

the deposit is a patina, an intersection, comes away to pass us a finger... How is it done?

put a rubber cap on the sensor and change it occasionally?

 

[Jari]

that I know mylar is a plastic material, so I would exclude the electrolytic phenomenon.
I also do not see how a plastic storage of the tub could affect the magnetic field generated by the sensor

the deposit is a patina, an intersection, comes away to pass us a finger... How is it done?

put a rubber cap on the sensor and change it occasionally?

Thanks for the answer, I would also exclude the electrolytic phenomenon due to mylar. However, the deposit of material, albeit from plastic, should be calcareous (because plastic is loaded with caco3).
to pass us a finger... I don't know why experiments are made abroad, however it is a patina that can be "grated" away.

I think the deposit affects the dielectric permittivity and therefore on the magnetic field. made is that when the sensor is clean it reworks.
(the residue is established after several cycles of operation).