I am in the process of working through my Supermax Aniliam Crusader M conversion to Mesa 5i25/7i77.
At this point, I'm bench testing everything on a table in the kitchen (why anywhere else?). I hadn't really thought everything through and thought I'd just pop an encoder on the spindle somewhere to work w/ the Automation Direct GS2 VFD, until I ran across John Thornton's Forum post referring to Jon Elson's webpage about not being able to find a good place to locate the spindle encoder. https://pico-systems.com/bridge_spindle.html How do I wire the Allegro sensor to the 7i77 board? I'm confounded on the pull-up resistor part of it... And, the values for the capacitor CL & Rpullup resistor at 5v vs 12v used in the data sheet. Allegro DATASHEET: http://www.allegromicro.com/en/Products/Part_Numbers/0667/0667.pdf Refer to Page 11, Figure 6, Typical circuit for proper device operation. Page 3, Output Rise time is based on resistor Rpullup 1K ohm and capacitor 4.7nF, Vpullup 12Vdc (of course 12vdc...). Digikey link: http://www.digikey.com/product-detail/en/ATS667LSGTN-T/620-1328-1-ND/2042758 FROM THE 7i77 Manual, p54: http://www.mesanet.com/pdf/parallel/7i77man.pdf ENCODER INPUTS INPUT COMMON MODE RANGE -7 +12 Volts INPUT TTL MODE THRESHOLD 1.4 1.8 Volts DIFFERENTIAL MODE IMPEDANCE 131 135 Ohms COUNT RATE ---- 2 MHz (With standard firmware/setup) WIRING? First off, this looks like a single-ended encoder setup, so I would move the jumpers on the 7i77 to the left-hand position for single ended operation. I would connect 5v of the encoder output to the Vcc for the sensor. (It does look like 12V would work for the sensor and the 7i77, giving better noise immunity, but getting 12vdc is funky and let's not go there unless needed). I am powering the 7i77 w/ external 5vdc, not from the 5i25. It doesn't seem right to connect Vpullup to the A+ input on the encoder inputs? What do I connect to the A+? Do I connect both Vcc and Vpullup to 5vdc? Also, how would Rpullup and CL change for 5vdc vs. 12Vdc? Lastly, might there be any suggestions on where to put the encoder on the spindle, like the back/top of the AC motor? I haven't really looked, but thought I'd ask. Maybe there's another location for it, but certainly not in the case like Jon Elson's sensors... Thanks, Mark ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
