see also: AntriebsTheorie, en/MotorCurves

MK3638 & MK3538

Photo

http://gallery.mikrokopter.de/main.php/v/tech/MK3638_001.jpg.html

http://gallery.mikrokopter.de/main.php/v/tech/MK3538d.jpg.html http://gallery.mikrokopter.de/main.php/v/tech/MK3538b.jpg.html

Version V2

https://www.mikrocontroller.com/images/MK36385V2_.JPG

https://www.mikrocontroller.com/images/3holemount_1.JPG

https://www.mikrocontroller.com/images/3holemount_2.JPG

  • 4 holes for propeller mount
  • for direct propeller mount

where to buy

The Motor is custom made for MikroKopter only. You can buy it here

Plate for direct carbon propeller mount here

Features

This motor has long wires (52cm), a short shaft and a small clipring. So it can be mounted directly on the aluminium arm.

http://gallery.mikrokopter.de/main.php/v/tech/MK3538e.jpg.html

Technical data

Voltage Lithium:

3-6

Current:

max 20A

Current max. (60 Sek.):

25 A

RPM/V:

760 Rpm/V

Wire resistance:

0,11 Ohm

Phase resistance:

0,07 Ohm

No-load Current:

0,65A @ 10V

Num. magnetic poles:

14

Propellers:

10" - 14"

Max. Efficiency (g/W):

7.36

Electrical power:

max 350 W

Thrust max.:

max 2200 g

Weight (only motor)

100g

Weight incl. cable and adapter

125g

Dimensions:

h=38 d=35 mm

Shaft diameter:

4 mm

Mounting plan

http://gallery.mikrokopter.de/main.php/v/tech/MK3538.jpg.html

Thrust over current

https://gallery3.mikrokopter.de/var/albums/tech/MK3538_characteristic_curve.gif?m=1409673363

MK3638 16V (4S) 12" Carbon

https://gallery3.mikrokopter.de/var/albums/tech/MK3638_4S_12Zoll_TvsI.gif?m=1418913043

https://gallery3.mikrokopter.de/var/albums/tech/MK3638_4S_12Zoll_TvsS.gif?m=1418913053

https://gallery3.mikrokopter.de/var/albums/tech/MK3638_4S_12Zoll_Efficiency.gif?m=1418913060

MK3638 4S 14" Carbon

https://gallery3.mikrokopter.de/var/albums/tech/MK3638_4S_14x45_TvsS.gif?m=1436461393

https://gallery3.mikrokopter.de/var/albums/tech/MK3638_4S_14x45_TvsI.gif?m=1436461385

MK3638 4S 15" Carbon

https://gallery3.mikrokopter.de/var/albums/tech/MK3638_4S_14x45_TvsS.gif?m=1436461393

https://gallery3.mikrokopter.de/var/albums/tech/MK3638_4S_14x45_TvsI.gif?m=1436461385

Different props

http://gallery.mikrokopter.de/main.php/v/tech/MK3538_characteristic_curve.gif.html

Same curve in higher resolution:

http://gallery.mikrokopter.de/main.php/v/tech/MK3538_characteristic_curve_0-8A.gif.html

APC Propellers

http://gallery.mikrokopter.de/main.php/v/tech/MK3538_characteristic_curve_APC.gif.html

13x6,5 APC

http://gallery.mikrokopter.de/main.php/v/tech/MK3538_characteristic_curve_APC13x6_5.gif.html

EPP-CF (chopped fiber)

http://gallery.mikrokopter.de/main.php/v/tech/MK3538_characteristic_curve_EPP_CF.gif.html

How to read the curves

With this curves it is easy to estimate the needed current and even estimate the flight-time.

You can read the needed current for each needed thrust

Example

The total weight of a MikroKopter (4 Rotors) is 1400g -> so each motor needs a thrust of 350g for hovering (1400g / 4 = 350g)

http://gallery.mikrokopter.de/main.php/v/tech/MK3538_characteristic_curve_0-8A_howto.GIF.html

Current needed for 350g with the 13x6,5 APC - Propeller? -> 1,8A

Current needed for 350g with the 12x8 APC - Propeller? -> 2,4A

The total current for all four motors would be 7,2A (4 * 1,8A) or 9,6A (4 * 2,4A)

Flight time

You can estimate the flight time with this formular:

Time = 54 * Lipo / Current

(54 because we estimate 10% losses -> 60 * 0,9)

In case we would have a 3300 Lipo (3,3Ah), the Flight time for the 13x6,5 would be:

Time = 54 * 3,3 / 7,2 = 24,7 min

The same for the 12x8 Prop:

Time = 54 * 3,3 / 9,6 = 18,5 min

That is a different of 33% in flight time!

See also: FlugZeit

Rotation direction

Clockwise (seen from above)

Connection:

  • A = gray
  • B = blue
  • C = black

Counter-clockwise (seen from above)

Connection:

  • A = blue
  • B = gray
  • C = black

difference MK3538 vs. MK3638

The technical data and weight are the same for both types.

http://gallery.mikrokopter.de/main.php/v/tech/MK3538a.jpg.html http://gallery.mikrokopter.de/main.php/v/tech/MK3638.jpg.html

Compared to the MK3538 the MK3638 has laser engravings and bigger ball bearings. The bigger bearings make the motor more silent.

http://gallery.mikrokopter.de/main.php/v/tech/MK3638Compare1.jpg.html

http://gallery.mikrokopter.de/main.php/v/tech/MK3638Compare2.jpg.html

Also the shrink tube (cable protection) is longer.




KategorieMotoren