# Apex Drive Lab PM Motors



## klmhayes (Mar 18, 2009)

Has anyone had experience with the Apex Drive Lab DD14 or DD25 PM motors? Has anybody looked closely at using them? 

Thanks,
Mark


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## major (Apr 4, 2008)

klmhayes said:


> Has anyone had experience with the Apex Drive Lab DD14 or DD25 PM motors? Has anybody looked closely at using them?


Hi Mark,

This was discussed a while back. 

http://www.diyelectriccar.com/forums/showthread.php?t=26622&highlight=apex+motor 

Bingo Sun Noon said he had used them, but he quickly fell off the face of the earth. I have not seen anything lately on Apex Drive Lab, so suspect they are gone.

Regards,

major


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## frodus (Apr 12, 2008)

and he never responded to either of us..... 

no proof, and he's done the same on other threads.... he's "built many controllers" and a BLDC hub motor for a motorcycle.... no pictures, no proof, nothing.


Apex is still in Portland, but I've not heard anything come from them in quite a while. have you tried contacting them?


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## klmhayes (Mar 18, 2009)

Thanks for the inputs! I will contact them directly and let you know what I find out.


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## Dennis (Feb 25, 2008)

Oh gosh, this is not the first time I saw posts on these "super PM motors". About a half year ago someone came here claiming they could take a series wound motor and replace the field coils with super magnets saying it would be more powerful than the series wound motor as is. I tried to explain along with Major on the waste of time of doing this and that PM's tend to be heat sensitive which weakens their magnetic field strength. I gave up on the guy, but Major asked him some question and the guy never came back since...


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## frodus (Apr 12, 2008)

Dennis,

They're not DC motors, they're BLDC motors (PMAC), and most of the heat is in the field windings (just like an AC motor).


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## Dennis (Feb 25, 2008)

> Dennis,
> 
> They're not DC motors, they're BLDC motors (PMAC), and most of the heat is in the field windings (just like an AC motor).



I was giving an example of someone who was talking about how their magnets where so superior to series wound motors which is electromagnetic. I was not referencing my post to permanent magnet synchronous motors here.


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## frodus (Apr 12, 2008)

Ok, I see that you were making an example, I just don't see how a series wound conversion to a PM DC motor relates to a BLDC motor at all.....


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## Dennis (Feb 25, 2008)

> Ok, I see that you were making an example, I just don't see how a series wound conversion to a PM DC motor relates to a BLDC motor at all....



Because I despise PM based motors. People flaunt them as though they are some super magical things when in actuality they are OLD tech. If PM's are so great then we would not need induction motors, wound field type rotor synchronous motors, or electromagnet field coiled DC motors. 

Permanent magnets are temperature sensitive, heat insulators which is BAD for a motor, and are easy to demagnetize from overloads on the motor which permanently changes the torque constant to a lower value causing more current to be drawn to achieve the same torque.

This is why I have no use for PM's. If a PM can be made to have the same Tesla field strength when cycled between -40 F to 160 F for 500 hours, conduct heat away, and not be easily demagnetized then I see PM's being something practical for traction motors.


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## frodus (Apr 12, 2008)

> Because I despise PM based motors.


good for you.


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