Hello stevec,
- No. Anyway, there is a chance you can get some kind of marking if you contact a magnet manufacturer to get customized magnets.
- No. There are several strategies, but the more accurate would be to use a magnetic angle or linear sensor to detect the magnet direction when it is being
mounted. - From my experience, there are no such standardized magnets with diametral magnetization. I suggest to look for magnet manufacturers in your area and contact them to see if they can make such magnets. It is likely they can.
- I could not find any. But maybe you will find this article useful: Using MagAlpha Rotary Magnetic Sensors in Side Shaft Mode | Article | MPS (monolithicpower.com)
Best,
Carmine