On 11/28/2012 12:21 PM, Peter C. Wallace wrote: > On Wed, 28 Nov 2012, Viesturs L?cis wrote: > > >> Date: Wed, 28 Nov 2012 18:49:30 +0200 >> From: "[UTF-8] Viesturs L?cis"<[email protected]> >> Reply-To: "Enhanced Machine Controller (EMC)" >> <[email protected]> >> To: "Enhanced Machine Controller (EMC)"<[email protected]> >> Subject: [Emc-users] 7i39 and brushless servo >> >> Hello! >> >> I am having difficulties getting 7i39 card to drive my servos. >> Motor datasheet is here: >> http://www.cutting.lv/fileadmin/user_upload/motor.pdf >> >> Motor is attached to first channel (motor 0)of 7i39 card, nothing is >> connected to the second channel (motor 1). >> >> All three jumpers are on the left side. >> >> I tried to figure out the Hall pattern and I _think_ it is pattern no: >> 44 from table in this page: >> http://linuxcnc.org/docs/html/man/man9/bldc.9.html >> >> Datasheet says that motor has 8 poles, and when I tried to turn it by >> hand, there were 8 positions that shaft tried to stick into, so that >> might be correct. >> What is puzzling me is the fact that during one revolution of motor >> shaft the Hall signals cycle 4 times. Is that correct? >> >> I tried to get the motor to spin this way: >> 1) disconnected encoder.0.position from axis.0.motor-pos-fb >> 2) disconnected bldc.0.value from pid.0.output >> 3) issued this command >> setp bldc.0.value 0.85 >> >> Motor did turn, but not really smoothly. But it did turn around >> instead of simply jerking back and forth. >> Currently there are CR2 and CR12 leds turned on as soon as I power on >> machine and CR8 and CR9(?) leds are turned on as soon as I "toggle >> machine on" with F2. >> >> Now I cannot get it to turn. If I turn it by hand, the feeling is that >> it has no power, but the 7i39 has motor power supplied. I checked. >> Encoder and Hall sensor signals are received - I can see them in HAL >> Meter (either bldc.0.hall1, bldc.0.hall2, bldc.0.hall3 or >> bldc.0.rawcounts are changing) as I turn motor by hand. >> >> It has no signs of life even though all the HAL settings are reverted >> back to what they were, when motor did turn: >> >> # BLDC module settings >> setp bldc.0.scale 4000 >> setp bldc.0.poles 8 >> setp bldc.0.pattern 44 >> # setp bldc.0.frequency 0 >> >> # Hall sensor feedback into BLDC module >> net motor.0.hall-1 hm2_[HOSTMOT2](BOARD).0.gpio.003.in => bldc.0.hall1 >> net motor.0.hall-2 hm2_[HOSTMOT2](BOARD).0.gpio.004.in => bldc.0.hall2 >> net motor.0.hall-3 hm2_[HOSTMOT2](BOARD).0.gpio.005.in => bldc.0.hall3 >> >> # position feedback signals >> # net motor.00.pos-fb hm2_[HOSTMOT2](BOARD).0.encoder.00.position => >> pid.0.feedback axis.0.motor-pos-fb >> net enc.0.raw hm2_[HOSTMOT2](BOARD).0.encoder.00.rawcounts => >> bldc.0.rawcounts >> >> # position command signals >> setp hm2_[HOSTMOT2](BOARD).0.3pwmgen.00.scale [AXIS_0]OUTPUT_SCALE >> # net motor.00.command pid.0.output => bldc.0.value >> setp bldc.0.value 0.85 >> >> net pwm.00-a bldc.0.A-value => hm2_[HOSTMOT2](BOARD).0.3pwmgen.00.A-value >> net pwm.00-b bldc.0.B-value => hm2_[HOSTMOT2](BOARD).0.3pwmgen.00.B-value >> net pwm.00-c bldc.0.C-value => hm2_[HOSTMOT2](BOARD).0.3pwmgen.00.C-value >> >> >> I would appreciate any suggestions, what might have happened. >> >> -- >> Viesturs >> > > What you did is not really good, you applied 85% of full motor voltage > continously before you had the commutation worked out. This will likely result > in overheating and shutdown of the 7I39, since you will get full peak current > out of the 7I39 with the motor efecctivly stalled (step motor mode). It > could have possibly damaged the 7I39 though this is not too likely. > > Peter Wallace > Mesa Electronics > > (\__/) > (='.'=) This is Bunny. Copy and paste bunny into your > (")_(") signature to help him gain world domination. > > >
Just curious Peter... but what would be a good value to start at? 10-15% or so? I don't have a 7i39 presently but I can see me getting one in the future. Dave ------------------------------------------------------------------------------ Keep yourself connected to Go Parallel: INSIGHTS What's next for parallel hardware, programming and related areas? Interviews and blogs by thought leaders keep you ahead of the curve. http://goparallel.sourceforge.net _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
