Hello,for you guys that are looking for large BLDC Brushless Motor ... data sheet coming soon for regular & halbach array version OEM welcome!

Views: 2062

Comment by Rick Yonika on June 1, 2017 at 7:54am

this might be the  motivation to get back to my super cub project !

going to need that data sheet

Comment by OG on June 1, 2017 at 7:57am

cool to hear that , working on data sheet coming soon.

Comment by Joe Renteria on June 1, 2017 at 9:01am
Nice. Looking forward to the specs...
Comment by Matthew R on June 1, 2017 at 12:49pm

What's up with the unit conversion errors? 50kw is 67 hp. 150 hp is 112kW. Or is it 150hp max, and 50kW max continuous or something?

Comment by OG on June 1, 2017 at 2:06pm
You can not got to google and just do KWH conversations! Motors do not work that way , you must supply KWh to voltage value as well at what RPM.
Comment by OG on June 1, 2017 at 2:24pm

for example or older smaller motor specs at 40kw

Any kv not higher than 80KV (35, 55, 80)
Large scale 40kw Brushless out runner motor for plane
The spec as following: 
MOTOR: S-154120 KV55
KV: 25, 35 ,55, 80
ESC: 400A/500A
NO LOAD CURRENT(20v testing voltage): 7A
RESISTANCE (mOhm): .140
SIZE: 154 x 115.54( without shaft )
Stator: 135*50mm
WEIGHT (kg): 5.9
SHAFT: 15mm Accessory pack: Yes
Internal PCB with 120 degree hall effect sensors

for example 5KW 96V Liquid Cooling High Power BLDC Motor the specs are for a motor 1/10 the power & rated around 60bhp.
Rated Power:3KW-7.5KW
Efficeincy: 91%
Phase Resistance (Milliohm): 6.2/48V; 12.0/72V; 36.0/120V
Phase Induction(100KHZ): 68uH/48V; 154uH/72V; 504uH/120v Speed: 2000-6000rpm (customizable)
Weight:11Kg(air),11.35kg(water); Casing: Aluminium 
Length (height): 126mm Diameter: 206mm
Keyway size: 5mm(W) x 43mm(L) x 19mm(D:22.3mm)

Comment by Gary McCray on June 1, 2017 at 4:53pm

Actually OG, I am pretty sure KW translates directly to horse power at least KW minus efficiency (heat) losses does.
And you are claiming twice the HP possible for a 100 percent efficient motor at the KW shown.

Lately it has become popular on vacuum cleaners and power tools and the like to completely fudge horsepower values with something called "maximum developed horse power".
I'm not really sure what it is but they are claiming 3 or 4 horsepower or more from appliances that plug into a 15 or 20 amp 110 volt AC circuit.

Maximum possible horsepower from a 20 amp 110 volt circuit is actually approximately 2 hp and then only if 100 percent efficient.

Watts actually combine voltage and current and represent power so variance in rpm or voltage is actually irrelevant as far as maximum power (KW or HP) is concerned except as caused by reductions in efficiency in the KWs generating the HPs.

Best Regards,


PS Brushless motors are magic, but not so magic that they can produce twice the shaft horsepower of the provided kilowatts.

Comment by OG on June 1, 2017 at 5:07pm
Cool you make your poin verry well but your not correct! Your looking at efficiency I am looking at BHP. this is how you do it for a electric motor ..
To find the electric horsepower of a motor, use the equation:
Horsepower = (Volts x Amps) / 745.7
(does not take efficiency into consideration)

Example: The electric horsepower of a motor with 120 volts
and 10 amps is:

HP = (120 x 10) / 745.7

Calculated out this gives an electric horsepower of 1.6092.
(rounded to the nearest 10,000th)
Comment by Gary McCray on June 1, 2017 at 8:13pm

Hi OG,

I am absolutely not disputing the formula you have provided as scientific measure horsepower is exactly equivalent to watts at the ratio you quote.

And at that ratio, 50KW is equivalent to 67.0511 hp.

And that does assume for an actual application (a specific motor) that it is operating at 100% efficiency with no mechanical, magnetic, heat or other design losses.

EG: there is no way a 50 KW motor can produce 150 horse power.

If it is a "perfect" motor it can produce a maximum of 67.0511 horse power and not a thousandth of a horsepower more.

And there are no "perfect" motors.

Matthew R's response above is totally correct.

And 20 amps at 110 volts = 2.95 hp at 100% efficiency (power factor of 1), but reality is most motors or motors plus speed controls seldom achieve better than about 80 percent efficiency so 2 hp is the maximum motor recommended for a 20 amp 110 volt AC service and normally drawing more mechanical HP than that will result in tripping the 20 amp breaker.

Unless I have missed something.

Comment by John Rambo on June 2, 2017 at 2:19am

Similar symbol, different meaning.
I'd guess the author has simply swapped KV (kiloVolts/RPM) with KW (KiloWatts)


You need to be a member of DIY Drones to add comments!

Join DIY Drones

© 2017   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service