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Czech AXI 4130/20 made by Model motors company on German brake

Dipl. Ing. Ludwig Retzbach in November sent me results of the AXI motor measurement. Ludwig Retzbach is very past master on E-powered models of airplane in Germany. He introduced so-called LRK outrun motor. He is the author of several specialized books and articles about battery, electric motors used in E-planes and about E-aviation at all. He leads group of E-model aviation in German union of model pilots DMFV and he is co-organizer of E-meeting in Aspach.

The motor measurement was realised on the brake. The brake on Retzbach´s apparatus is operating to max. torgue of 1,3 Nm. Ludwig Retzbach has permitted kindly me to present his measurement of motor AXI 4130/20 for 24V with speed controller JETI Mater 77A opto (timing2). This configuration is used with my full satisfying from spring of 2003 in my Piper J3 Cub and SpitfireMk2A presented on these sites too.

About motor AXI measurement L. Retzbach reported on December 13, 2003 on "Elektroflug-Symposium" in Swiss Winterthur and prepares the article in the special E-issue of "Modellflieger". I try to arrange the reprint of this translated article in RCR.

Umot / V

Imot / A

M /g*10cm

f / Hz

n / min-1

M /Nm

P in / W

Pout / W

eta

24.0

10.0

261.0

117.0

7020

0.2560

240.00

188.73

0.79

24.0

15.0

425.0

114.6

6876

0.4169

360.00

301.01

0.84

24.0

19.8

591.0

112.4

6744

0.5798

475.20

410.55

0.86

24.0

24.9

751.0

110.2

6612

0.7367

597.60

511.48

0.86

24.0

29.9

916.0

107.9

6474

0.8986

717.60

610.84

0.85

24.0

35.0

1084.0

105.9

6354

1.0634

840.00

709.47

0.84

24.0

40.1

1231.0

103.6

6216

1.2076

962.40

788.18

0.82

24.0

42.7

1305.0

102.6

6156

1.2802

1024.80

827.50

0.81

24.0

50.0

Does not brake anymore

 

For better clarity I realised graph from sheet of measured data. It can be shown this motor is good designed for sports flying, because the top of the efficiency curve is very flat and its maximum lies in current range from 15 to 35 A. This range is mostly exploited.