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Author Topic: help with step/direction vfd lathe spindle  (Read 8550 times)

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help with step/direction vfd lathe spindle
« on: February 23, 2012, 12:07:33 PM »
machine is a converted 12x36 lathe 2axis (xz)
mach turn
C11-G bob
2hp 3phase motor  3500rpm
hy series vfd   =  http://www.ebay.com/itm/120705048710?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

my mach mill will run the motor fine with the same vfd.
the lathe vfd is set up 100% the same settings and seems to work fine.

i punch in the same motor tuning in turn and it is nothing like the mill.
i tryed this guys method and it kinda helped me tune it some.
http://www.machsupport.com/forum/index.php/topic,18580.0.html

the problem is i can get the top speed right on but it is not linear or correct at say half speed.
i am not sure on how to adjust the motor tuning to get the speed right or close thru out its range.
all of the spindle tuning parameters are very confusing to me.

i check the bob for 10v on full powert and it says 5v ish????
it seems i need some way to tune the pot on the bob and then start the spindle tuning.
i have a rpm tach on the spindle so i can see real rpm no problem.
any help is welcome. thanks

Offline Fastest1

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Re: help with step/direction vfd lathe spindle
« Reply #1 on: February 23, 2012, 12:58:18 PM »
I read that yesterday and it worked very well for me. I am getting within 75 - 100 rpm of requested with no tach or spindle index. I was having the low voltage output too on 1 of my C6's but I really think that was due to my inept testing in which I probably fried a voltage regulator of some form. Until that issue is solved most of the rest will be useless. You say you run the same thing on your mill? What is the voltage output on that one? I know that Arturo at cnc4pc told me to put "1000" steps per in the spindle tuning box but Art says to use "60". Maybe both ways work but get there by different means? I do know that after I did Art's suggestions and redid step 2 as suggested (a few times) it is very close.
I want to die in my sleep like my grandfather, not like the passengers in the car! :-)

Offline Fastest1

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Re: help with step/direction vfd lathe spindle
« Reply #2 on: February 23, 2012, 01:01:13 PM »
Btw, "this guys method", IIRC I believe Art is the creator of Mach :-)
I want to die in my sleep like my grandfather, not like the passengers in the car! :-)
Re: help with step/direction vfd lathe spindle
« Reply #3 on: February 23, 2012, 01:10:04 PM »
great
i figure i must have missed something but have no idea what.
Re: help with step/direction vfd lathe spindle
« Reply #4 on: February 23, 2012, 01:12:10 PM »
i get 10v ish on the mill just fine
i dont get how turn can send out 5v and get full power on the vfd

Offline Hood

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Re: help with step/direction vfd lathe spindle
« Reply #5 on: February 23, 2012, 02:19:36 PM »
Just wondering if you possibly have the speed in spindle pulleys set wrong?
Hood
Re: help with step/direction vfd lathe spindle
« Reply #6 on: February 23, 2012, 03:05:55 PM »
well, i see 60 on the vfd and i have the tach readings. this is what i set my pulley speed to.

Offline Fastest1

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Re: help with step/direction vfd lathe spindle
« Reply #7 on: February 23, 2012, 03:10:39 PM »
Set your pulley speed to 1000 for setting up, then measure your speed when an S1000 command is given
I want to die in my sleep like my grandfather, not like the passengers in the car! :-)

Offline Fastest1

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Re: help with step/direction vfd lathe spindle
« Reply #8 on: February 23, 2012, 03:11:32 PM »
Going down in 50 rpm increments via S command, when does the rpm change? What was the max speed your spindle was doing on S1000?
I want to die in my sleep like my grandfather, not like the passengers in the car! :-)
Re: help with step/direction vfd lathe spindle
« Reply #9 on: February 23, 2012, 03:22:44 PM »
with the pulley on 1000
motor tuned to 60 step / full velocity full accel / 1 in both pulse boxs
the vfd comes down about 180rpm