Re: [CAD_CAM_EDM_DRO] Re: PWM stepper driver with external bridge

Tim is correct. I have a few prototypes but didn't proceed with the 1/4 step
because it looks like the servo systems are just better.
Dan
-----Original Message-----
From: Tim Goldstein <timg@...>
To: CAD_CAM_EDM_DRO@egroups.com <CAD_CAM_EDM_DRO@egroups.com>
Date: Sunday, January 07, 2001 9:40 AM
Subject: RE: [CAD_CAM_EDM_DRO] Re: PWM stepper driver with external bridge

>Alan,
>
>> Dan Mauch's design, for example, uses an F84 for logic, will run up to 40
>> volts and gives 1/4 step resolution. While rated for 5 amps, it could
>> likely run close to 10 with just a wee bit of tweaking.
>
>I know Dan was playing with a 1/4 step unit, but as far as I was aware he
>has not put it into production. Am I missing something here??
>
>> 2. You cannot expect that the "inbetween" steps in a
>> microstepping controller
>> to be at all accurate and as the number of intermediate steps
>> goes up, so does
>> the error. ( Ericcson/NJR has a useful app note describing the
>> problem )
>> If your aim is higher resolution, you would do better to use 1/2
>> or 1/4 step
>> and different pulleys to gain the increase.
>
>This is a very good point that I think is often overlooked. It seems that
>many people I have communicated with think that a microstepper will give
>greater resolution.
>
>Tim
>[Denver, CO]
>
>>
>> FAQ: http://www.ktmarketing.com/faq.html
>
>
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