PCB layout offer.
Hi Jan Rune,
I have been laying out PCBs since red/blue tape a knife.
I have various XMT units here for mechanical details.
I have lots of in depth design of BLDC unts to 2KW.
The SX3 motor is quite reliable. Mine has done close to 2000 hours at full speed.
I am happy to give you some feed back on the design.
It is always better to get a second opinion, than making ... version E.. Now that one works.
I can do the PCB layout if you like, SMD or conventional. I think mixed is the way to go.
As you can see from the post #64, the circuits are quite close to what is there.
Also the motor overload circuit is just that from what I can gather. It needs to be on every edge of the PWM cycle to work properly.
Proper current limited, current mode operation like the MC33033/35 (chip on earlier controller) can be made to work properly.
I have current mode designs using this chip that have been running for years. The just a simple PIC interface is needed to alleviate the stupid button pushing - beep.. beep.. beep.. concept used and sending the signals to the display will still work (within the limits of the stupid display limits)
If you want to go down the path of the full BLDC design you must use current mode and a PIC that has 3 or 4 PWM independent outputs.
Then you can go from full fast fwd to to reverse on the current limit.
Using the MC33039 tacho chip might even allow spindle sync for tapping but it needs to designed in from the beginning.
Do it once and do it right, and this will make the SX3 pretty good.
I have an ATC on the drawing board, and it doesn't use precious table space, but that is another story.
PM me, with your email address and I will send some MC3303x circuits, and I can send you a few chips too test with if you wish. I have some spares.
And while I am at it an external speed over-ride potentiometer, or even using the up down arrows for over-ride the Mach3 controlled speed would be very useful
Super X3. 3600rpm. Sheridan 6"x24" Lathe + more. Three ways to fix things: The right way, the other way, and maybe your way, which is possibly a faster wrong way.