strange cell problem

[Steveaff]

Hello after a bit of help, I have a Pantera self cleaning chlorinator that is approx 3.5 years old, the salt is at 6000 ppm with is what is recommended by the manual and all other chemicals and in normal ranges. The problem is I am unable to get any current though the cell, I have used the correct cleaning fluids with out any changes, as last resort I gave the cell a quick clean with a bit of sand paper, and now I am able to full current though the cell for approx 5 to 6 hours and then the current once again drops off to nothing, The question is, is the cell just u/s and I need to get another one? or is there something in the water coating the surface of the cell? The only thing that has been added lately is copper for algae control could this be coating the cell
Thank you for any help

[Pool Helper]

What is the pool water's (calcium/ total) hardness level? Often these chlorine generators tend to increase the hardness of the water, and (especially) with a high pH the electrodes tend to get plated up.

[mrmike]

Is there a way to tell if plating is the problem? My pool hard hardness up to almost 700ppm (I just bought the house) and consistantly high pH.

System (Pure&Clear) was working in warm months, and is supposed to shut down when water temp less than ~ 55F, but now it's is not working at all. I tried to use an ohm meter on it, and I think that the connection from the wires to the plates are 'bad', that is, no continuity.