[Solved]Hard Disk motor control...

Hi all, I've dismantled an old hard disk and I would like to have it spinning without the electronic cards that was given with.

I've read here and there that this can be achieved using an ESC controller for RC brushless motors. My problem is that the motor has 4 connections pins and the controller 3.... On the net I've found informations regarding the connection option and one speak about 3 coils pins and one common/ground.

Let's name the connections A, B, C and D.

Using my multimeter, I found the following values : Between A and B I've found 5.8 Ohms. The same between B and C. But I've found 3 Ohms between A & D, B & D and C & D.

Am I right if I say that the 3 coils connections are A, B & C, in a star scheme with D as a center point ? (But should I not find 6 Ohms in place of 5.8 Ohms in that case ?)

Any information will be welcome.

By the way, I wish you a pleasant year 2013 full of health, love ...and arduino projects !

Best wishes,


PS: Please excuse my poor English level...

Looks to me like you can just ignore D and connect the ESC to A, B, and C.

Ok... Thanks John... I'll try this option.

Happy New Year,


Hi John,
Just to let you know that it works perfectly !
Thanks a lot and best wishes for 2013 !!!