spindle with low and high gear ratio

[visky]

Hello!


I have spindle controlled with 0-10V VFD ( sensores vector control drive ).

Spindle has got two gear reductions. On low it drives from 255 - 1048RPM and in high gear ratio from 1 - 255 RPM.

I would have two outputs on mesa IO board .

How can i configure hal to turn on high gear when RPM is <=255 and turn on low gear when RPM is > 255 RPM

ini file

LOW_GEAR = 0.00954 ( 10Volts/1048 )
HIGH_GEAR = 0.039215 ( 10Volts/ 255 )

Also, it is posible to configure and use PID for RPM ? . In this situation i wouldn't neet to use gain for high and low reduction.

I have got 1024CPR encoder on spindle and it is configure for velocity and works just fine if i use G95 code.

It give me 4096 pulses / revolution.

Thanks

[Big John T]

You might be able to use motion.spindle-speed-out to choose but your range can not overlap.

John

[chester88]

Need more info. Do you want hal to swich gear ratios on the fly or will you use a g code to select range? Am I to assume you have a physical gear change or are you using a fancy two speed motor? There are examples of gear change routines in EMC's example configs. Mazak I think . Ask your question on the emc users mail list you'll get more/better answers.

[visky]

No it is not two speed motor but physical gears.
Jes i know there is an example called ' mazak demo ' . I have wached this example but my configuration would be diferent. Similar but diferent :-).

What i would like :

When i would have in my ngc file speed in range from 0 to 254 RPM EMC will turn on high gear reduction
- when speed will be in range from 255 to 1048 RPM EMC will turn on low gears reduction.

I think the best will be if i would use PID for this. Because , EMC will be hunting motor.speed-in * 60 . This way i will have +/- 1 rev resolution. If i would use gain i would have +/- 5 rev .

[chester88]

Hi ok starting to understand. Now using a g code to select a range is in my mind a better idea. This way you preselect the gear range and don't have to worry about the time it takes to shift gear. Again I have to presume a bit because you have not been specific enough-that you mean you want to detect the S speed and if it is above 254 then switch gears. I assume you are not using a lathe (meaning constant surface speed). (My limited knowledge of) industrial CNC machines always have a way to select a range (if there is a manual transmission).
Ok you could use classicladder or a HAL component connected to 'motion.spindle-speed-out' which controls the current spindle rpm request. detect if the requested rpm is above/below the 254 limit. set a feed-hold, change gears, set the scaling, and release feed hold.
if you do rigid tapping and the speed crosses that boundary bad things will happen.
Yes EMC can use PID with the spindle drive-it has been done.
Again more ideas will come from the mail list.