3 Axis Driver from Univelop

[Injuhneer]

Originally Posted by freemen Well I got one too (Univelop Board !!!) and I can only get it to work under KCAM 4 but the motors are not folowing the jog commands properly they jump all over the place....beter than no output from Mach3, I can't seem to figure out the correct pin out for the parallel port!!! Got 5 V 500ma for control, and 12 V 6A for steppers ! Any Help would be appreciated especialy with the Mach3 setup !!! Thank's Free

The Univelop web site has a document with their pinouts and logic.

I had similar issues when the motors would move. A high amount of squealing and chattering at low speeds often resulting in no movement at all.

[papagolf]

I fired up the machine last night and for the first time it moved under control of EMC2! ok excitements over. +12vdc for the motors is painfully slow. I couldn't get EMC2 over .2in/sec without stalling with the univelop board. so I borrowed a 24vdc supply from work and got it up to .5in/sec(almost .6/.7 but stalled in a few spots on the leadscrew). this will give me rapids in the 30ipm range so I'm not too upset. anyone made the leap to 36vdc? the chips datasheet listed 36 as the max so I was hesitant to push my power supply any more then 24 because its only rated for 4 amps and I have 3 1.5 amp motors... it got a little warm. good luck!

[freemen]

Ok here is my setup of the dreaded Univelop board... I finally got it to work under EMC2 no problems under linux at all but since I am not to good with linux well decided to do a fresh install of windows XP again from scratch on a 40 Gig hard drive, and only installed the basic setup and Mach 3. But it still would not work and I finaly did the (optimizing windows install for mach 3 ) file and the problem was found to be
Quote-------------------------------------------------------------------
9. Set Computer to Standard PC NOT ACPI PC
NOTE: This is only necessary if you wish to remove ACPI AFTER install.
If you followed step 0, you don't need to do this.


1. Right Click My Computer and select Properties
2. Click Hardware tab.
3. Click Device Manager Button in the middle.
4. Double click "Computer".
5. Right click on Standard ACPI PC and choose Update Driver.
6. Choose "Install the software from a Specific Location (Advanced)"
7. Click Next.
8. Choose "Don't search. I will choose driver to install."
9. Click Next.
10. Choose "Standard PC" from the listing.
11. Click Next.
12. Click OK.
-------------------------------------------------------------------------
and now I finaly get a pulse frequency of 23 to 25 khz that is now stable on the diag page of mach3 !!!!!

so the setup is pretty easy from here 4.5 volts 500ma for control voltage
24 volts 10Amps power suply from a dead canon lazer printer (free)
and different size stepper motors that I get from a recycle place close to my place (see pics )

So good luck with your set up it took me 2 weeks to figure it out but finally got it!!!
Any questions.....Just ask I will do my best.....Ièm new to this also....but a lot of reading helps!!!

[papagolf]

I managed to borrow a 0-32v 5a power supply from a buddy and hooked it up last night. I turn up the volts to about 26, ran good... 28 even better... 30 I've never seen my leadscrews spin that fast! I was absolutely elated!!!! that is until sparks flew from the univelop board, the ammeter pegged on the power supply and fire erupted from one of the TA8435's(oddly the one that wasn't moving). As cool as this was to witness(kinda like a train wreck in slow motion) it is now blatently obvious that this board is NOT capable of 36(or 30 for me) volts as advertised. After doing some reading on the TA8435H. The ABSOLUTE MAX motor voltage is 40v. the recommended max is 26.4. It is also advertised for 2.5A and that is again an absolute max. 1.5a is the rated load. Good for a small machine IMHO. We will see what customer service has to say on this one! More to come...

[pminmo]

Motor bemf in all likely hood killed it.

[papagolf]

I could see that on the one motor/drive I had in motion(y-axis), but it was the X and Z-axes that were enabled but static. Even now I can still move the y-axis but the X/Z are dead(probably has something to do with the missing chunk from the chips . The only other thing I can ponder is the setting of Vref for the 8435's. looking over the datasheet I would appear to me that changing Vm(in my case increasing) would require an increase in resistance to counter the whole ohm's law thingy.. as resistance stayed the same, voltage increased and so must the current. just did the math... assuming there is no dynamic compensation for current(I'm no expert here), 24v at 1.5a gives us 16ohms. increasing voltage to 30(given same resistance)
current increases to 1.875A RMS and 2.65A Peak. both values beyond the specs of the TA8435. still doesn't explain why the static axes burned up but I think I'm headed in the right direction. possibly holding current at 1.875A for 15-20 minutes?

[pminmo]

bemf added to the supply voltage. As why the active channel didn't blow could be different mfg batches, ir voltage drop, active mosfets conducting, among other things. Toshiba's are very supply sensitive, I've seen them blow because a low esr motor supply cap was 1/4" farther away than another.

[zjutiger]

Here is the setup to test Univelop CNC board,

It works for me in Jog-on model, both for forward (CW) and backward (CCW) continuously.

The most important part is in part C:
_____________
C. This step is the most important step

In our computer the following setup for z-axis makes both “CW” and “CCW” to work.

In order to turn a motor with MACH 2/3,
1. click “z axis” button,
2. move velocity make the following cover.
You can also change the value of “steps per”, “accel”, “step Plus” and “dir pluse”
3. click “save axis settings”
4. click “ok”
__________

Because it tunes your motor with software and the driver, you really should try different parameters in this part C to make sure your motor is tuned to your computer.

After tuning, the configuration in the cnctest.pdf does work for our univelop 3-axis driver board and Dell computer and a 4-wire bipolar step motor.

Thanks lots,

Julia

[lancut]

"I was absolutely elated!!!! that is until sparks flew from the univelop board, the ammeter pegged on the power supply and fire erupted from one of the TA8435's(oddly the one that wasn't moving). As cool as this was to witness(kinda like a train wreck in slow motion) it is now blatently obvious that this board is NOT capable of 36(or 30 for me) volts as advertised."

That is so true for this board, @30V the static axis Z failed. Did not bother to email the seller because they won't answer it. There is no phone number to talk to somebody so I decided to replace the failed chip myself, waiting for the shipment... I'm real good at soldering because that's how I earn my living... more to follow

[TigerPilot]

I too had bought these boards without reading here first. Now that I have them I can only say DON'T BUY IT. I ended up putting HUGE heatsinks to run my steppers.

Did use the info here on this thread to get my machine running. Thanks to pminmo.

Yoram