Rewind HK5020 to 370-400kv for Logo600SE

[augur]

Hi.

I like to rewind my 5020 to better match my Logo600SE with 12s. It has 450kv and should have 370-400. Is it fine from tuning perspective to simpy add a turn. It has 15 turns.

Or is there a better method to lower the KV and use thicker wire? 16 turns are much. I actually rewinded simple delta with ABC scheme only.

Cheers
Nils

[omerco]

I'm running my rewound Pyro 440KV with 14T pinion at 2100 HS on 690SX with 700mm blades, hard 3D.

If you intend to fly with similar spec you don't need a rewind your motor will do the job.

If you aim for lower HS you will have less stress on the gear so you can go with 13T (i started with 13T and 1900HS - no problem).

If you still insist - then consider 400. i don't think you need more than 14T to be safe of keeling the gear. I know of a pro who used 12T with 4525...

Adding 1 turn should be 420KV, adding 2 397KV. As you probably know, the lower you go you will have more resistance and less efficiency...

[augur]

Actually I running 1750 HS with 11T. The Jive can handle the low PWM but it is not perfect. Thats the reason I like to reduce the KV. (More power would be fine also. :-) )

[omerco]

OK i see your point. I'm running the same PWM (throttle %) by the way with castle

Considering 13T pinion:

Y is also an option - 10T for 390kv. 11T for +-355kv with 14T pinion.

YY would require 20T for around 380 KV with the same PWM you are using now, but the question is how thin the wire will be. could still be the best option for lower resistance but you need to know wire thickness for the options to decide.

[augur]

http://www.modelbouwforum.nl/forums/...8-post497.html

Good example for YY. Could made this with 1.08 wire perhaps. Not an expert with rewinding yet. With Y I have to rewind normal Delta and only connect the ends? 10 turns per arm?

[omerco]

Good solution from Dekker. Why not try it with the same wire? 1.25 will not be difficult. YY will give you much less resistance then Y. close to 1/4.

EDIT - sorry my mistake confused between 450 and the 350 you are looking for.

[augur]

Some suggestion what to wind to reach 380? 10+10 with YY?

[omerco]

If you take the example you posted:
19T: 442KV
20T: 19/20*442=420
21T: 19/21*442=400
22T: 19/22*442=380

Have to say I'm surprised as Dekker result doesn't fit the data you posted: 450KV for 15T. are you sure your data is accurate? did you MEASURE the KV and count the turns? if you took the number of T from scorpion it is incorrect and has 2 more probably.

You can maybe contact Dekker directly to consult about that motor. he has a user in this forum as well. helped me a lot with my rewound Pyro.

[powercroco]

pls. consider, 5020 was built with 2 different statorshapes during the times - they generate different n spec of course!

[omerco]

I checked Scorpion data - says 15T which usually means its 17T for real. that fits Dekker's data.

Ralph - what do you think about rewinding to such low KV?

[powercroco]

no problem to do this.
just built "evo" type with 8+8YY and 14pole can for 390/V
but consider, that you will get a short and steep efficiency curve.

btw. pyro 800 is also 5020 14pole.

and in direct comparison 5020size has 12% less working area as 4525size.

[augur]

Would it theoretically better to run it at low PWM instead?

As I understand YY 10x11 could be a good scheme or perhaps 9x12? Is there a difference in KV or only easier to handle?

[omerco]

Originally Posted by powercroco

but consider, that you will get a short and steep efficiency curve.

That, was actually the question

and in direct comparison 5020size has 12% less working area as 4525size.

How do you calculate that? surface of the outer side of the stator? and how do the magnets count?

[omerco]

Originally Posted by augur

As I understand YY 10x11 could be a good scheme or perhaps 9x12?

If i remember correct something Ralph Pointed (somewhere...) - the 9x12 will give slightly lower KV over the 10x11.

[augur]

That would be the smallest problem.

[augur]

Does anybody know a good scheme calculator? The calculators I used are offline (website based) and every die I found with help of Google do not support YY schemes.

[omerco]

http://www.bavaria-direct.co.za/scheme/calculator/

But you want to use Ralph's scheme with 6 small groups. see "Dlrk evolution" here for delta:

http://www.bavaria-direct.co.za/sche...n/#prettyPhoto

Or this for YY:

http://www.scorpionsystem.com/buildi...ld_and_review/

[apostolosnt]

If you get 20 turns in there you will get 420 kv but you probably have to go to 1.27mm wire.
This is a 5020 wound with 1.4mm 8+8 YY 525kv.
(kv shown are measured on jive. At 18* add around 10kv to each number)



You can consider a Wye termination and get about 350kv with 12 turns with 1.6 wire for an easy wind.