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Weiss VM32 CNC Conversion

DavidR8 said:
May I reach out to you if I run into major isssues?
Click to expand...
The number you have reached is out of service.
Your call is very important to us, please stay on the line until an expert becomes available...... (I'm trying guys;-) )

Just kidding, absolutely call, might be worth calling now because I can at least convey some of the snags that I ran into.

Please post details of the servos you are using, not sure how similar or different they are to the ones I'm using?

I think you have my number.

BTW Purolator just dropped off a package.
 
slow-poke said:
The number you have reached is out of service.
Your call is very important to us, please stay on the line until an expert becomes available...... (I'm trying guys;-) )

Just kidding, absolutely call, might be worth calling now because I can at least convey some of the snags that I ran into.

Please post details of the servos you are using, not sure how similar or different they are to the ones I'm using?

I think you have my number.

BTW Purolator just dropped off a package.
Click to expand...
I have three DMM DYN2 drives, two 640-DST-A6TK1 motors for the X and Y axis and an 86M-DHT-A6MKB for the Z axis.
The attached manual for the drives is pretty good.
The issue I was having yesterday was with the Z axis.
I could get it to move but only briefly before the driver threw a "Lost Phase" error.
 

Attachments

Chatted with the DMM semi-tech person. He thinks maybe the motor with the brake might not have been calibrated properly.
Apparently I may be able to reset this myself by jumpering some pins and power cycling the drive/motor. Stay tuned.
I may also have a bad drive.
 
DavidR8 said:
Chatted with the DMM semi-tech person. He thinks maybe the motor with the brake might not have been calibrated properly.
Apparently I may be able to reset this myself by jumpering some pins and power cycling the drive/motor. Stay tuned.
I may also have a bad drive.
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Well I would certainly do as DMM suggests.

That being said that alarm appears to get generated when the driver thinks the motor is 90 degrees or more out of position for > 2 seconds. So as a realty check I would try making the motor turn in very small increments say 10 degrees at a time and just see what happens, does it error out after 9 bumps?

Assuming the motor turns or attempts to turn, If the encoder signal is compromised (check the encoder cable) that would likely cause this error. I know there is a warning label on mine warning not to jar the shaft, sounds like the encoder might be fragile perhaps it took a hit axially?

Are you testing this with no load?

What is the part # of the drive?

Looks like your drives use a 60Vdc source (mine require 220Vac). What gauge wiring do you have between the power supply and Z-drive?

Any chance the brake is engaged? That would certainly do it, on mine I had to hookup an external relay to drive the brake circuit and there are parameters for PU and DO time of that relay. Don't forget the brake is engaged by default (no power). If you have not added the relay for the brake, don't forget the FWD across the relay coil.
 
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Problem solved @slow-poke
The DMM tech (who I think is in Hawaii on vacay) sent me the attached document.
Problem was that the driver (which I randomly picked out of the three that I have) for the Z axis was set to 5 poles and the Z-axis motor is 4-poles so it wasn't sending the right number of magic pixies to the motor.
Using the software noted in the pdf I changed the number of poles for the Z-axis driver to 4, saved the new parameters, rebooted the drive and presto, a perfectly running motor.
Then I took the drive that I thought was faulty, read its parameters and it was set to 4 but the X and Y axis motors are 5-pole hence it errored out when I was testing the driver with the motors I knew worked.
Had I selected the drive set to 4-pole for the Z-axis it would have been fine <eyeroll/> But I can sleep better know that I can proceed with getting the enclosure together.

Though I don't quite understand how to do the relay for the brake.
 

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140mower said:
DRAT!!!!!! Well done! I didn't think this was going to hold you back long. :cool:
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Hah!
Issues like this with all things electronic kinda drive me crazy. It immediately makes me doubt all my abilities and then I want to pitch the new, unknown to me tech and switch to something I know and understand like steppers instead of servos.

I never get that feeling with mechanical issues but electronics are real blind spot for me.
 
DavidR8 said:
Hah!
Issues like this with all things electronic kinda drive me crazy. It immediately makes me doubt all my abilities and then I want to pitch the new, unknown to me tech and switch to something I know and understand like steppers instead of servos.

I never get that feeling with mechanical issues but electronics are real blind spot for me.
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..... and now you can understand why I daily drive a '78 Ford truck...... :p
 
I agree He’s incorrigible!
IMG_1416.jpeg
 
Every day is a learning day in the DavidR8 shop.
After struggling to get the Z-axis servo brake circuit working correctly yesterday (and generally feeling like crap physically), this morning I came out to the shop, had another read through the manual, tore all the drive and relay wiring down and started from scratch.
Recording this here for future generations (aka, me when I have to put this all into the enclosure.)

Power supply:
DC- to brake DC-
DC+ to relay COM
Relay NO to brake DC+

DC- to relay DC-
DC+ to relay DC+
Relay jumper set to LOW

Driver:
Pin 7 to power supply DC-
Pin 9 to relay IN

And with that, I have fully functioning drives ready for to be put into the enclosure.
Happy days.
 
DavidR8 said:
Every day is a learning day in the DavidR8 shop.
After struggling to get the Z-axis servo brake circuit working correctly yesterday (and generally feeling like crap physically), this morning I came out to the shop, had another read through the manual, tore all the drive and relay wiring down and started from scratch.
Recording this here for future generations (aka, me when I have to put this all into the enclosure.)

Power supply:
DC- to brake DC-
DC+ to relay COM
Relay NO to brake DC+

DC- to relay DC-
DC+ to relay DC+
Relay jumper set to LOW

Driver:
Pin 7 to power supply DC-
Pin 9 to relay IN

And with that, I have fully functioning drives ready for to be put into the enclosure.
Happy days.
Click to expand...
And here I thought it was that you had trouble getting out of the ugly Christmas Sweater in that picture of you that @Tom O posted. ;)
 
jcdammeyer said:
And here I thought it was that you had trouble getting out of the ugly Christmas Sweater in that picture of you that @Tom O posted. ;)
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Here's the brake circuit wiring diagram.
1734631108591.png

What screwed me up was this advice: "Use dedicated power supply for brake control. Do not share with any other device"
So I connected the relay power to a separate power supply.
But this diagram only works if pin 7 is connected to the DC- of the power supply that is providing the DC+ to the brake.
I don't understand why but I do not question the magic pixies when they work!
 
Make sure you have a free wheeling diode across that relay coil!

If you don't that output is going to get pooched. When the driver turns off, the collapsing field around the could generates a back EMF (voltage spike) that can be several hundred volts and that short spike will kill the opto sooner rather than later.
FWD.jpg
 
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David,
Yes, across pin 7 & 9 (The Cathode (banded side), to the + side pin 9)

The diode is connected reverse bias so current only flows through the diode for a few ms whenever the relay drops out, otherwise it's as if it's not there. So instead of the voltage building up to a damaging spike, as soon as it gets to about 0.7V, the diode conducts and dissipates the energy from the collapsing field back into the relay coil. Almost any diode would do, say a 1n4007 or whatever you have on hand. Any diode with say a 100V or greater rating and 1A or so. I would not activate that output until you install the diode, your playing with fire.
 
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