Rule of thumb, and you can adjust this frequency as all pool water chemistry can be different from pool to pool with regard to calcium, IOW, i have no idea where your chemistry is, so, the following is sort of a blanket statement:
Do a visual inspection of the cell once every 2 months. It doesn't take any special training (you can do it yourself), and it takes about a minute to do, the inspection that is. If you need to clean, that can take a bit longer, and involves the use of acid. So if you have a pool guy, make him do it (if he isn't already)...
4 parts water, one part acid. Soak for 30 min. If you have a lot of build up, you can use something NON-METALLIC to help break it up with. I use bamboo pot stickers...GENTLY, you don't want to force the plates apart.