On Tue, Jun 19, 2007 at 12:03:30AM -0500, RogerN wrote: > I plan to use spindle speed control in my part programs. I also would > like to use the best spindle gear selection for the proper cutting speed > and to best utilize the horsepower I have available. If my part program > sets a spindle speed of 500RPM, how will EMC2 handle it if I'm in a gear > where top speed is 600RPM vs a gear where top speed is 1800RPM? I guess > my basic question is do I have to define my top speed for each spindle > gear change? Is this done in the part program, perhaps similar to a > tool change?
There are so many ways to deal with this - we'd probably each want something different. If you can sense the gear you're in with some switch or prox, and get that information into HAL, you could use a mux and scale blocks in HAL to manipulate the motion.spindle-speed-out value before feeding it to your PWM generator or DAC. Then, you get the proper motor speed for the specified S word. The demo_mazak configuration does something like this (and it also knows how to change its own gears - without changing the commanded S word, you can switch gears and the speed adjusts for the new gear. I think it also asserts feedhold during the change. Most of this is done in the ladder logic.) I've been told that an operator will want to select a gear range before starting the program, and auto gear changes are best avoided because it's not an exact science determining when to switch a gear. For instance you probably have a lot of overlap between ranges. If you're using constant surface speed on a lathe, you sure don't want to stop and change gears during a facing cut! But what you want to do really is up to you. There are no hardcoded restrictions - you get the commanded spindle speed on a HAL pin and you can do anything you want with it. Chris ------------------------------------------------------------------------- This SF.net email is sponsored by DB2 Express Download DB2 Express C - the FREE version of DB2 express and take control of your XML. No limits. Just data. Click to get it now. http://sourceforge.net/powerbar/db2/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
