Efficiency of Lehner motors

[Hayden]

Does anyone know what the Efficiency of the Lehner motors are?
Does it vary from size or kv of the motor?
I think every model of motor is different they will have a different sweet spot where it has its max efficiency at a certain rpm...etc..

[Sylvester]

The sweet spot for lehners are around 35K.. I think they are 85% efficient under partial load, maybe Rene or somebody else could scope in on this.

[Hayden]

I think their over 90% efficient but I could be wrong
I think that’s one of the reasons why lmt motors are so expensive

[Sylvester]

They are very efficient. They are expensive for several other reasons ;

Hand wound
Segmented magnets
Made id Germany :)

GERMAN ENGINEERING IN DA HOUZZZE! ;)

[MetalMan]

Efficiency will vary a bit. Factors include voltage, wind, load, etc. I imagine the efficiency range for our use will range from 60%-90% with the Lehner motors.

[Hayden]

I was referring to the efficiency % that they state in the specifications so I can compare motors.
Isn’t it the efficiency that counts mostly?

If these lehner motors are so good (and they are!!!) why don’t they supply specification with them? When I got mine and I just got the motor in a tube and that’s it:030:

[Serum]

Nope, efficiency is one thing, but it needs to be at a certain load.

Here, check this site;
http://lehner-motoren.com/motordia.php?la=en

[GriffinRU]

I guess it is not clear how to use my program...

[Serum]

This is measured data, not calculated.

[GriffinRU]

Originally Posted by Serum

This is measured data, not calculated.

Measured only key motor parameters, the rest is calculated as well.

[BP-Revo]

I randomly clicked one of the 1940 specs and efficiency was 91%...damn.

[Serum]

Measured only key motor parameters, the rest is calculated as well.

I have got no idea what you mean.

[GriffinRU]

Originally Posted by Serum

I have got no idea what you mean.

To create motor profile you need motor constants. Motor constants can be measured or calculated, last one requires a lot of input parameters. But most motor manufactures specify motor constants, which they obtain from testing, while during design phase they use calculation to figure out how to create one with parameters they type into model.

To create graphs you need motor Kv, I no load, I max, Resistance. To create more sophisticated graphs you need to add inductance, inertia and core parameters. But for RC applications the first 4 constants will do the job of defining efficiency, power, torque and current draw.

As reference you can check any motor manufacture datasheets for motors or even Lehner excel spreadsheet where you can click on cell and check for math behind. I was trying to bring all motor data under one roof :)

[BrianG]

I want a 110% efficient motor...

[BP-Revo]

Originally Posted by BrianG

I want a 110% efficient motor...

111 here.