Michael James wrote: > >Hello group... I need to replace a broken Glass Scale/Encoder but I >don't have a useful part number. It still works but an end got >crushed. How can I figure out what resolution it is? I've got an >oscilloscope, is there any other test equipment I'd need? > OK, since it is still working, hook the scope to one of the quadrature outputs (A,B) of the scale, and make a short move. Count the number of pulses generated. You will see a burst of pulses with the pulses in the center of the burst coming the fastest, due to acceleration/deceleration. The resolution of the scale will be equal to the number of pulses divided by the length of the move. For instance, if you see 25 pulses for a move of .1", that would mean a resolution of 250 cycles/inch. In quadrature, that would give 1000 counts/inch, but linear scales are usually sold measured by cycles/linear unit. If this is a very old unit with inch-based scales, you are in "deep Doo-Doo", as no manufacturer has made native inch scales in the last 25 years.
It is also possible that the scales are analog, and you will see sine waves, not square pulses. These are still available, but an interpolator device refines the measurment to a finer degree. Some of these scales produce voltages, some produce a varying current. It will be a bit more difficult to mix and match analog scales, but it can still be done. Jon Addresses: FAQ: http://www.ktmarketing.com/faq.html FILES: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/files/ Post Messages: [EMAIL PROTECTED] Subscribe: [EMAIL PROTECTED] Unsubscribe: [EMAIL PROTECTED] List owner: [EMAIL PROTECTED], [EMAIL PROTECTED], [EMAIL PROTECTED] Moderator: [EMAIL PROTECTED] [EMAIL PROTECTED] [EMAIL PROTECTED] [Moderators] URL to this group: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO OFF Topic POSTS: General Machining If you wish to post on unlimited OT subjects goto: aol://5863:126/rec.crafts.metalworking or go thru Google.com to reach it if you have trouble. http://www.metalworking.com/news_servers.html http://groups.yahoo.com/group/jobshophomeshop I consider this to be a sister site to the CCED group, as many of the same members are there, for OT subjects, that are not allowed on the CCED list. NOTICE: ALL POSTINGS TO THIS GROUP BECOME PUBLIC DOMAIN BY POSTING THEM. DON'T POST IF YOU CAN NOT ACCEPT THIS.....NO EXCEPTIONS........ bill List Mom List Owner Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
