No, of winding and size wire

[Jason Wilkinson]

Hi again, In Hugh Piggott's 2009 english edition his 14 footer calls for 52 turns 2 in hand  #14 wire (only one grade magnets are listed IE N40) I want to try a 14 footer  but my magnets are 2x1x3/4. question 1) what would be the equivelent turns of #14 or #16 for 24 volts. Q 2)what problems am i likely to face if i increase the mags to 20/disc still 24 volts

 Jason

[Flux]

If you use thicker magnets and don't change anything it will lower the cut in speed and you will hit stall in fairly low wind. You could considerably increase the air gap to get things back to the same but you are using more expensive magnets to no advantage.

You could cut the number of turns and use thicker wire and get more out of it and it may or may not stall in high winds, if it did you would need a bit of line resistance.

I haven't got those plans and you give very little information but I assume it uses 16 magnets. If you go up to 20 you will need to change to 15 coils to get it to work. You will already have made it rather powerful by using thicker magnets, increasing the number as well will make it a poor match to the original blades and it would really need bigger blades to see any benefit from the money invested in more and bigger magnets.

You could run it at 14 ft if you chose the turns to get cut in right but you would need a fair bit of series resistance to keep it from stalling. It would be a very tough alternator for a seriously windy area but otherwise not a very cost effective way to go.

Flux

[Jason Wilkinson]

THanks flux i forgot to mention my mags are n50,i do understand the relationship between number of magnets and number of coils,#14 wire seems a bit difficult to get, but i do have #16 and was considering 60 turns 2 in hand. the disc size is 18 ins

[Flux]

For the single layer winding the number of coils is 3/4 the number of poles.

Two in hand #16 is heavier than #14 and will also be easier to wind. If you increase magnet thickness, number of poles and go up in grade from N40 to N50 you will need much less turns than the specified winding. You will probably manage 3 # 16 in hand.

If you are keeping to 14ft I wouldn't advise increasing number of magnets. Going thicker and up in grade will get you well down on the number of turns. I suggest you do a test coil at something like half the recommended number of turns as a starting point.

Flux

[Dave B]

Jason,

  Take a stab at what you think will be close for a coil, wind it, then test it. Do this and the math until you have a coil you are satisfied with to duplicate for all in your stator.

  Wind them up, wire them up and cast your stator. It's your machine, have fun.  Dave B.