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O.S. - OSMG9524 OSM51011204 51011204 531028154124 4531028154124
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O.S. .25 Brushless Motor 3820-1200W
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O.S. .25 Brushless Motor 3820-1200W
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Tech Notes
This is the 3820-1200W .25 Brushless Electric Motor from O.S. Motors.


For .20 - .25 size airplanes
Stainless steel prop shaft projects on either side to allow front
or rear mounted applications
Two front bearings
Rigid rear mounting design
Centrifugal fan design with angled ventilation holes draws air
through the motor and across the windings and magnets for improved
Two year limited warranty through Hobby Services beginning at date
of purchase


.25 Brushless Electric Motor with Backplate, four Phillips Head
Mounting Screws, 3mm Gold Plated Male Plugs attached to leads,
three 3mm Female Plugs with Shrink Wrap, Prop Adapter and
Instruction Sheet


60A brushless ESC


Rated Power: 440W
Rated Voltage: 11.1
Rated Current: 40A
Maximum Current (5 sec): 75A
No Load Current: 1.9A/10V
Phase Resistance: 21.4 miliohms
Phase Inductance: 11.4
Maximum Efficiency: 85%
kV: 1200
Poles: 14
Turns: 10
Shaft Diameter: 0.20" (5mm)
Shaft Length: 0.45" (11.5mm)
Weight: 5.64oz (160g)
Lead Wire Length: 3.5" (90mm)
Lead Wire Gauge: 17AWG
Length of Motor Can: 1.7" (43.3mm)
Diameter of Motor Can: 1.47" (37.5mm)
Length/rear of Motor Can to Prop Washer: 2.3" (58mm)
Prop Washer Diameter: 0.87" (22mm)
Thickness of Motor Mount: 0.12" (3mm)
Width of Motor Mount: 1.96" (50mm)
Height of Motor Mount: 1.96" (50mm)

Performance for this motor with different props and LiPo cells is as
follows (all data with 60A ESC, and APC props):
Prop Size Voltage Current Watts Thrust Cells RPM
9.5x7.5 12.6 44A 554 2.2kg 3S 12,000
9.5x8 12.6 48A 605 2.3kg 3S 11,800
9x6 16.8 48A 1,025 2.5kg 4S 15,600
10x6 12.6 47A 592 2.0kg 3S 11,900
10x7 12.6 52A 655 2.2kg 3S 11,600
11x5 12.6 54A 680 2.0kg 3S 11,400
11x6 12.6 60A 756 2.3kg 3S 11,100
11x7 12.6 62A 781 2.4kg 3S 10.500
10x5E 12.6 42A 529 1.8kg 3S 12,200
10x7E 12.6 53A 668 2.3kg 3S 11,500
11x5.5E 12.6 54A 680 2.4kg 3S 11,500
11x7E 12.6 62A 781 2.7kg 3S 10.900
12x6E 12.6 66A 832 2.8kg 3S 10,400
12x8E 12.6 75A 945 2.9kg 3S 9,300


Nomenclature is defined as follows:
0MA means 0.S. airplane motor
First two digits are the rotor diameter
Second two digits are the length of the magnets
Last digits indicate the kV of the motor

jxs 11/08/13

– If you need more information, use these O.S. resources –
Email: enginesupport@hobbico.com
Web Site: http://www.osengines.com/
Phone: 217-398-8970
  Postal Address:

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