# Calculating number of coil turns for a generator

I'm building a generator for a school project. I'm planning to use N42 neodymium magnets with performance of 5100 Gauss, How do I calculate what diameter of copper wire I need to make the coils and how do I determine the best number of turns for that particular set up?

• Are we talking about a permanent magnet AC generator? What's the $μ_r$ of the core? What sort of budget are we talking about? Commented Nov 8, 2018 at 23:00
• Yes it will be a permanent magnet AC generator. I believe the relative permeability would be 1.05. My budget is \$100. Commented Nov 8, 2018 at 23:05
• Okay, with a budget like that I have to ask, do you want a "generates usable power" generator, or a "demonstrates the principles behind generator operation" generator? The former may be hard at that budget; the latter less so. Commented Nov 8, 2018 at 23:06
• "I believe the relative permeability would be 1.05." What, you're using plastic with a pinch of rust stirred in? Ferrites for high RF have $\mu_r$ of 10 or so, steel is effectively around 200. Commented Nov 8, 2018 at 23:34
• As it stands this question is too broad, to engineer a motor takes a knowledge of books of information. Best thing to do at this point is experiment Commented Nov 9, 2018 at 16:36