PNC3 Starturn / SMCU Starmill Bipolar/Unipolar

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paragon
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PNC3 Starturn / SMCU Starmill Bipolar/Unipolar

Post by paragon » Mon 04 Apr , 2011 16:01 pm

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
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Re: PNC3 Starturn / SMCU Starmill Bipolar/Unipolar

Post by paragon » Mon 04 Apr , 2011 22:32 pm

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

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Steve
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Re: PNC3 Starturn / SMCU Starmill Bipolar/Unipolar

Post by Steve » Tue 05 Apr , 2011 9:55 am

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.

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Re: PNC3 Starturn / SMCU Starmill Bipolar/Unipolar

Post by Denford Admin » Tue 05 Apr , 2011 14:02 pm

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

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