Re: PWM motor control from USB I/O board [TANKS]

[dwconn404-at-comcast.net]

Thanks a lot, Joe. That's good to know.

 

This USB board has open collector relay drivers built into the DO channels. I think they'll sink 50ma per channel, but I don't have the specs handy. The PWM is open collector, too, but it's easy to modify if that won't work for the SSRs. This thing may actually be a good option for WiFi based motor speed control.

 

      Doug

> -------------- Original message -------------- 
> From: Joe Sommer <anvilus9-at-adelphia.net> 
>
> > 
> > Doug, 
> > 
> > At 02:33 AM 5/5/2006 +0000, dwconn404-at-comcast.net wrote: 
> > >I'm hoping Joe Somer or another motor control guru can answer this for us. 
> > >What do you say ? Is 1KHz acceptable for a PWM signal ? 
> > 
> > My controllers use 1 KHz PWM. 
> > 
> > 1 KHz should be OK until you get to about 6000 rpm = 100 rev/sec. 
> > 
> > It sounds like four opto-isolators driven by four of your digital outputs 
> > can drive four SPDT automotive relays for FWD-OFF-REV of two tracks. 
> > Adding two D1D40 SSRs driven by your two PWM signals should be 
> > able to provide proportional speed control. 
> > 
> > Joe 
> > 
> > 
> > ********************************************** 
> > Joe Sommer, Anvilu
> s Machine Works 
> > 2378 Nantucket Circle, State College, PA 16803 
> > 814.234.4773 anvilus9-at-adelphia.net 
> > http://www.anvilus.com 
> > 
> >