On 9/28/2011 2:55 PM, Bruce Klawiter wrote: > I was looking at this encoder, > http://www.usdigital.com/products/e2#description > It says: > Tracks from 0 to 100,000 cycles/sec > 32 to 1250 cycles per revolution (CPR) > 128 to 5000 pulses per revolution (PPR) > > I don't understand the difference between CPR and PPR, I am thinking it has > something to do with the A and B channel being 90 degrees out of phase. If > that is the case why is the PPR 4 time higher and not only twice as high. You can monitor the rising and falling edges of both a and b channels giving you 4 times the resolution. > Also does any one have a recommendation for an encoder, what is a good > reliable brand, what CPR or PPR should I get. The high the line count the > better I would assume. I think the rule of thumb is to make sure you have at least 10 times more counts than the smallest resolution you want to maintain. More never hurts, but if you have too many the frequency at rapid speed is going to be high causing noise and monitoring issues.
I have had good luck with dynapar encoders, there not cheap tho. > > Read about my conversion here: > https://sites.google.com/site/bmklawt/home > > Regards, > Bruce > > ------------------------------------------------------------------------------ > All the data continuously generated in your IT infrastructure contains a > definitive record of customers, application performance, security > threats, fraudulent activity and more. Splunk takes this data and makes > sense of it. Business sense. IT sense. Common sense. > http://p.sf.net/sfu/splunk-d2dcopy1 > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users -- PowerTech Repairs and Contracting LTD. 3-9452 193a St Surrey, BC, V4N 4N4 Ph: (604) 882-3850 Fax: (604) 882-3851 ------------------------------------------------------------------------------ All the data continuously generated in your IT infrastructure contains a definitive record of customers, application performance, security threats, fraudulent activity and more. Splunk takes this data and makes sense of it. Business sense. IT sense. Common sense. http://p.sf.net/sfu/splunk-d2dcopy1 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
