PNC3 Starturn / SMCU Starmill Bipolar/Unipolar

[paragon]

Am I correct in assuming that the PNC3 Starturn steppers are Unipolar (8-lead) ULN2803A driven where as the Starmill SMCU are Biplolar (L297)?

If so what was the reason(s) for Denford to go the unipolar route rather than bipolar on the Starturn?
I was under the impression that Bipolar is more desirable for higher torque, is this correct?

Additionally does anyone know the torque rating of the Starturn stepper oz/in or Nm?

Kind Regards,
SRG

[paragon]

Hello All,

I mistakenly thought the LCB3 was using unipolar but on closer inspection it is indeed using bipolar.
I didn't notice the motor four wire connections (red,orange,black,yellow) at the top of the LCB3 card for the X and Y axis's.
I have also since noticed the stepper driver heat-sink located behind the controller card.
Does it use the L297 IC's to drive the steppers?

Kind Regards,
SRG

[Steve]

Hi,

I was going to ask what control card was fitted but it sounds like its a smartstep or Denstep.

Either way they use L297 and L298 SGS driver and output chips set to 1.9A

The 2803 darlington pair chips are used for the machine outputs.

[Denford Admin]

This machine is a NEE control board.
I've put a bit more NEE info on here recently, so the answer may be in those pdf's