More 540C-7XL inside pics

[zeropointbug]

Just a few more pics inside... thats one compressed coil!

[captain harlock]

Strange, even the Feigao incorporates a segmented rotor, too....hmmm.

BTW, zeropointbug, if you want to add more pics, you dont need to open up a new thread. Just click "post reply" and then choose " manage attachement".

[zeropointbug]

I would think that segmented rotors would be less expensive, maybe?

Pretty dang simple though! Hmmm, why are they still more expensive than brushed motors? They are mass produced enough that you'd think they could bring the price down even further.

[captain harlock]

Actually most segmented motors are the Highend ones, which cost lots of money.

[zeropointbug]

hmmm, that is interesting. ;)

[SpEEdyBL]

That's not very many segments for a segmented rotor. The lehners have 10 or more.

[zeropointbug]

Really, 10, are you sure? Maybe the magnets are typically of the higher grade then the smaller ones. Like N48 grade, i think are the highest grade for 80' C currie temperature. Then there magnet grading in the 100, 120, 150, 180, and 200 C range. Those are the high end ones, i would think they are using 150, prob 180C temp magnets?

[SpEEdyBL]

I saw a picture of a lehner rotor. I didn't get an exact count, but there were a lot of segments each less than 1/8 inch thick.

[zeropointbug]

Really, hmmm, i wonder what the benefit is going that way. Maybe it gives more consistent magnetic field? I think they have 6 poles total, if i'm not mistaken?

[BrianG]

The use of a segmented system reduces magnetic flux "eddy" currents, which are losses. Instead of having large eddy currents in a solid core, you have a bunch of much smaller ones, which apparently is better. Which is the same reason pwer transformers use many plates instead of a solid core. This page explains it.

Using segmented system may also have something to do with reducing hysteresis, but not quite sure on that. It's been a LOONG time since I was in shcool studying magnetic theory.

[neweuser]

Originally Posted by BrianG

The use of a segmented system reduces magnetic flux "eddy" currents, which are losses. Instead of having large eddy currents in a solid core, you have a bunch of much smaller ones, which apparently is better. Which is the same reason pwer transformers use many plates instead of a solid core. This page explains it.

Using segmented system may also have something to do with reducing hysteresis, but not quite sure on that. It's been a LOONG time since I was in shcool studying magnetic theory.

From my understanding, having more segments would create better efficiency and less resistance with better flow of "eddy" currents. the more segments that are used, the better the conductivity creating less loss? Did I understand that right?

[Serum]

Using three thick slices doesn't make it a 'segmented magnet' The feigao's use this as following;

1 core for the s
2 cores for the L
3 cores for the XL

[zeropointbug]

BrianG, right, i don't know why i didn't think of that! Duuuh ;) Honeywell has magnetic core that has 10,000's of laminates, then with ton's of force it's squeezed to together with resin. They are suppossed to have super low losses, if you put a NIB magnet inside them, you can't even attract a small nail to stay on it...

Serum, that's what i was think for the Feigao motors...

[Serum]

The 'normal' 7XL uses the same compressed coils bytheway..

[zeropointbug]

Serum, ya i know. Do you know if the Hacker do the same? THey must, they are pretty much identical...

Does anyone have any thoughts on the Hacker compared to the Nemesis motors? Hacker pretty much started the brushless car market (not intentionally)