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Author Topic: CS Labs CSMIO/P-A  (Read 15177 times)

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Re: CS Labs CSMIO/P-A
« Reply #330 on: September 11, 2018, 01:46:41 PM »
Hi

Craig
Making my own drive is way above my level and a route I am not prepared to take.

Hood
Thanks for your comments. There is a reference to Master/slave in the manual but very limited info.

I think this is a none starter going by both of your comments or at best something which will cause more issues than its worth.

I'll reluctantly stick with the phase converter and order a 3 phase motor.

Thanks again.

Mick

Re: CS Labs CSMIO/P-A
« Reply #331 on: September 11, 2018, 09:03:57 PM »
Hi Mick,
go on......where's your sense of adventure!!! There's nothing more exciting than having 585V DC link
capacitors discharge in front of your face in a shower of sparks, smoke and molten metal.

It makes your heart pump really fast....and thats got to be good for your health. ;D

In truth its not quite as difficult as it seems, there is a large body of published literature on the subject
of active PFC.
Depending on your drive you could instead of hooking three phase wires to it hook two DC wires of your home brew
boost PFC single phase DC power supply. I work for a company that repairs industrial welding equipment
I could walk around the workshop and pick up all the secondhand parts I need within the hour. A $50US
Texas Instruments Lauch XL microcontroller board and your in business, and I wouldn't be stopping at 3kW,
I'd be aiming at 5kW cont and 10kW 10 sec overload.
My wife left with my best friend...
     and I miss him!
Re: CS Labs CSMIO/P-A
« Reply #332 on: September 14, 2018, 01:02:27 AM »
Hi Craig
Lol. It's a nice idea but not at the moment. I'll give you a shout if I change my mind.

Any idea why I'm getting slight movement when the drives are enabled? Auto tuned the drives but not tuned the CSMIO yet.

Cheers
Mick
Re: CS Labs CSMIO/P-A
« Reply #333 on: September 14, 2018, 03:25:23 AM »
Hi Mick,
your servos are in velocity mode. An analogue voltage at the input will cause the servo to rotate. It is tunable, something like
300 rpm per volt. Even when there is no input voltage there is still electrical noise, thermal noise if nothing else, that's a fact of physics
and you could end up with some net small voltage which will cause rotation.

When you hook up the CSMIO it will close the position loop. Thus if Mach commands 3184 steps, say, or 114.6240 past the index point and
should the servo drift a few tenths of a degree due to noise then the CISMO will detect that the servo is not at its commanded location and make a voltage
correction such that the servo moves back towards 114.6240 again.

If your servo were in position mode it would not rotate at idle, the position loop is now in the servo drive but it has the same result as the CSMIO, namely any drift
will be detected and a restorative action will be taken by the drive.

Craig
My wife left with my best friend...
     and I miss him!
Re: CS Labs CSMIO/P-A
« Reply #334 on: September 14, 2018, 01:44:56 PM »
Thanks Craig

The motor is turning at about 3 rpm without any voltage connected. With the DC motors this was adjusted by the potentiometer on the drive. I will read through the manual tuning section to see if anymore info is given. Doesn't say anything regarding this using the autotune method. I understand what you saying regarding closing the loop but seems a lot for the CSMIO to keep correcting.
Please forgive me if that was a stupid comment.
Cheers
Mick
Re: CS Labs CSMIO/P-A
« Reply #335 on: September 14, 2018, 03:40:18 PM »
Hi,
3 rpm represents an effective input voltage of:
Vin=3 /300 (rpm/V)
   =0.01V or 10mV

That could be the input bias voltage of the input amplifier alone. You can chase your tail for hours and then the temperature changes and its out
again. Close the position loop already!

Craig
My wife left with my best friend...
     and I miss him!
Re: CS Labs CSMIO/P-A
« Reply #336 on: September 16, 2018, 02:53:25 PM »
Hi

Good news so far nothing blown up. lol

As mentioned before without any power connected to the Vref I get very slow movement of about 3 rpm. Not a major issue.
Connected up to the CSMIO on Dac output 0. Pins 1 and 14 on the Analog I/O connector. When I enable the drive the motor turns at around 60 rpm. I have around 200mv on pins 1 and 14 without any speed command.

I have autotuned the drive without the CSMIO connected which worked fine.

Craig
I take on board what you said about the CSMIO closing the loop and rectifying this issue but this is not happening. I am unable to autotune through the CSMIO. It is making it impossible to try different setting within the drive when it moving the motor at approx 300mm/minute as soon as enabled.

I am also not able to index the motor. If I do a reference home from Mach the motor moves in the right direction but ignores the home switch.  

Any Ideas

Cheers

    
Re: CS Labs CSMIO/P-A
« Reply #337 on: September 16, 2018, 03:00:30 PM »
Hi,
the CSMIO is not working as it should.

Do you have the means, either an oscilloscope or software within the CSMIO to monitor the synthesized encoder outputs from the drive?

Another idea just to test would be to disconnect the CSMIO altogether and set the servo drive in position mode. The manufacturers servo loop
is going to be a snap by comparison to closing it with the CSMIO.

Craig
My wife left with my best friend...
     and I miss him!
Re: CS Labs CSMIO/P-A
« Reply #338 on: September 16, 2018, 03:15:42 PM »
Hi
I haven't got an oscilloscope but there is one within the CSMIO. I wouldn't have a clue what I am looking for.

What would you suggest doing once I put the drive into Position mode?

Mick
Re: CS Labs CSMIO/P-A
« Reply #339 on: September 16, 2018, 05:01:50 PM »
Hi,
if you wish the CSMIO to close the loop then the servo drive will have to produce encoder signals
to the CSMIO correctly. That is the first step, you must confirm that the servo drive is producing
the right encoder signals.

If you put the servo drive into position mode, then without pulse input  the servo should stop and
stay that way. It confirms that the position loop is providing a correction such that the velocity is
zero and overcoming the slight bias voltage.

If you had a simple step/direction controller, even a plain parallel port you could control your servo
easily.

Craig
My wife left with my best friend...
     and I miss him!