10-04-2017, 01:13 AM
Hi
I am new here but i know where to find the answer.
Problem #2. Sleep mode. These calipers go into sleep mode after 5 minutes of inactivity and the only way to wake them up is to re-power. Moreover after they come back from sleep mode they show zero reading. These problems make using these calipers very impractical in DRO applications, how one can be confident that reading is correct and not frozen? After short experiments with calipers I found that changing mm/inches display mode by pressing caliper's button prevent them for falling into sleep. It means if button is repeatedly pressed in less than 5 minutes intervals, caliper remains active. Of course it would not be much difficult to automate this process by adding extra wire and modifying the OpenDRO software to send periodically logical pulses to the button. This was my first thought. Fortunately I've found much simpler solution: to automate this using internal pulses. I connected data line (see http://groups.yahoo.com/group/ShumaTech/photos/album/64668936/pic/list) to the inch/mm input with a short wire inside the caliper body. Now it is switching inch/mm display mode quite often (thousands times a second) synchronously with data line output. The good thing, it does not affect caliper reading! I don't know how reading looks like on LCD display, since I removed it, but I see no changes when reading caliper via DRO-375. Now it works great. It never goes to sleep!
Conclusion: by applying simple modifications described above, the inexpensive HF calipers become a good choice to use them with Shumatech DRO. Very low jitter even if digital filter is off, pretty good accuracy, and high immunity to electromagnetic interference.
-Alexey
I am new here but i know where to find the answer.
Problem #2. Sleep mode. These calipers go into sleep mode after 5 minutes of inactivity and the only way to wake them up is to re-power. Moreover after they come back from sleep mode they show zero reading. These problems make using these calipers very impractical in DRO applications, how one can be confident that reading is correct and not frozen? After short experiments with calipers I found that changing mm/inches display mode by pressing caliper's button prevent them for falling into sleep. It means if button is repeatedly pressed in less than 5 minutes intervals, caliper remains active. Of course it would not be much difficult to automate this process by adding extra wire and modifying the OpenDRO software to send periodically logical pulses to the button. This was my first thought. Fortunately I've found much simpler solution: to automate this using internal pulses. I connected data line (see http://groups.yahoo.com/group/ShumaTech/photos/album/64668936/pic/list) to the inch/mm input with a short wire inside the caliper body. Now it is switching inch/mm display mode quite often (thousands times a second) synchronously with data line output. The good thing, it does not affect caliper reading! I don't know how reading looks like on LCD display, since I removed it, but I see no changes when reading caliper via DRO-375. Now it works great. It never goes to sleep!
Conclusion: by applying simple modifications described above, the inexpensive HF calipers become a good choice to use them with Shumatech DRO. Very low jitter even if digital filter is off, pretty good accuracy, and high immunity to electromagnetic interference.
-Alexey