"New build" Acorn swap in

[Spartan117]

I have done dozens of systems with those drives. They perform much more reliably set to 5v and connected to the DB25 header. It's not so much the voltage as they require the line driver signal. The screw terminals are open collector

This was the main posting I didn't understand really
I am not an electronics-guy anyway, so I am not sure what this means, plus the translation loss from english to german.

I don't get where the difference is, if I switch the gnd or the 5v+. I thought there are optocouplers in the drives and so they should act like LEDs? So it shouldn't make any difference if you switch the one or the other line to that LEDS in it?

[fbx]

Ok, picking up where I left off -

1. I anticipated the VFD wiring throwing me a couple challenges - had one fault (fault 9030) which was corrected by changing the NO/NC assignment of input H1 IN5.

2. After correcting, I am not getting any response when I call the VFD with m3 sxxx. Also not getting any response when I call the VFD from the manual control menu. The VFD was not responding prior to the correction of fault 9030 or after the fault was corrected.

The VFD did respond correctly to the VFD bench test video, using the 2-wire control (0-10v) and a jumper from DCM (VFD common) to FOR (forward run).

VFD settings:
1. I have not yet altered any of the VFD settings that I had for a 2-wire (0-10v) operation. When performing the VFD bench test, the 2-wire VFD settings worked fine (except during power off cycle - power off would cause a short 1-2 second activation of the VFD and spindle, spindle would spin for about a second then turn off as the VFD turned off).

2. Looking at the wiring from the Huanyang schematic - I did not use the P and Pr since I have no braking resistor.
3. Added FOR/REV/RST/DCM - VFD settings: PD044: 02 (forward rotation), PD045: 03 (reverse rotation), PD046: 14 (reset), DCM = digital common terminal
4. Added FA and FB - VFD settings: PD052: 03 (fault indication)

VFD that I am using: Huanyang HY series 4kW

Is someone else out there using a Huanyang HY series VFD? Did you wire your VFD according to the schematic? If so, would you mind sharing your settings or possibly reviewing mine if I post them from PD000 to PD185?

I feel like the non-responsive VFD is either a setting or a terminal that shouldn’t be hooked up (looking hard at FA and FB terminals)

Thanks!

[fbx]

Got it.

I missed the relay output assignment for FOR/REV/RST. Once those were assigned it worked perfectly.

Now to calibrate the 0-10v signal to the RPM range of the spindle.

[fbx]

Having some trouble getting my y-axis overall turns ratio dialed in. I performed the steps as noted in Marty's thread, still coming up a little off kilter.

1. DM542T stepper driver - steps per revolution = 3200 (I set this, did not change it)
2. Sent command to each axis to move 5" (so I can still measure with my calipers)
X-axis moved 0.9800 inches
Y-axis moved 0.9290 inches
Z-axis moved 0.9800 inches

Using the spreadsheet calculator:
X-axis at 0.9800 inches = 5.10204 rev/in
Y-axis at 0.9290 inches = 5.38213 rev/in
Z-axis at 0.9800 inches = 5.10204 rev/in

3. Next, I used these 3 values to determine max rate for each stepper motor / driver
X-axis at 5.10204 rev/in has a max rate of 735 in/min
Y-axis at 5.38213 rev/in has a max rate of 696.75 in/min
Z-axis at 5.10204 rev/in has a max rate of 735 in/min

4. I reduced the acceleration for all axis from 0.5 to 0.8 because the max rate was simply too much. I had a motor stall? out. I plan to work out the max rate vs acceleration once the revs/inch are taken care of

5. After plugging in the new rev/in values, I zeroed all axis and ran a test to see how close they were to being correct. Once they are close, I'll finish the process using a dial indicator to get the values closer.

I zeroed then sent the same 5 inch command to each axis, results as follows:
X-axis travelled 5.024 inches
Y-axis travelled 6.240 inches - the Y-axis is the odd one out.
Z-axis travelled 5.015 inches

Note - since I am only using a straight edge and a pen to make tick marks, both the X and Z axis may be closer.

6. Going back into the setup wizard, I also notice that the max rate values for X, Y, and Z have changed to some crazy number. This happened yesterday as well for the Y-axis. When I tried to change the Y-axis max rate, I was not allowed to enter any values larger than 494 (prompt window said so).

Overall the X and Z axis are acceptable to me. These can be fine tuned with a dial indicator. However, I am not sure where to begin troubleshooting the y-axis.

Additional info:
Machine style is traditional 3-axis mill with y and x at the table, z on the column\
Stepper motors and drivers - detailed in first post - used the Acorn DM series stepper driver schematic
No limit switches installed at this time
Huanyang VFD installed - used the Acorn Huanyang VFD schematic - (Y-axis responds the same way whether the VFD is on or if it is off). Shielded VFD cable approximately 4 feet away from shielded motion control cables
No other accessories hooked up



Any ideas? Report and screen shot attached

[suntravel]

related reading:

https://centroidcncforum.com/viewtopic.php?f=63&t=1801

Uwe

[fbx]

related reading:

https://centroidcncforum.com/viewtopic.php?f=63&t=1801

Uwe

This is what I used, and I followed each step.

I also downloaded and used the spreadsheet calculator for determining corrected overall turns ratio.

Is there something in this thread that I am missing?

[suntravel]

I assume you have 16x5mm ball screws

25,4/5=5,08revs per inch if your steppers are 1:1 on the screws.

I don´t think they have more power than for 1000 rpm : 1000/5.08 = 196,8 in/min max rate

You must know the pitch of your screws, than it is easy.

Finetunning is an other thing, but needs a high resolution dial indicator.

Uwe

[fbx]

I assume you have 16x5mm ball screws

Yes, they are 1605 ball screws

25,4/5=5,08revs per inch if your steppers are 1:1 on the screws.

Steppers are attached directly to the ball screws, so 1:1 ratio. With the stepper driver set at 3200, a 1 inch command gives 1 full rotation.

I am unclear about what the 25,4/5=5,08 means. Is this 25.4 mm (1 inch) divided by 5 mm (pitch) = 5.08 revs per inch?

I don´t think they have more power than for 1000 rpm : 1000/5.08 = 196,8 in/min max rate

Not sure what you mean. Where did the 1000 rpm come from?

I used the formula in the thread. DM542T drivers show 200kHz in the specs, so I calculated it as:
3200 steps per rev times 5.10204 turns per inch = 16,326.530 steps per inch linear travel **Note** the 5.10204 turns per inch is coming from the downloadable spreadsheet in the thread. Since I am using a pen to make tick marks, I can accept that 5.08 is probably what I need. The 5.10 is likely from measurement error. But it doesn't explain why my Y-axis is not anywhere near that value.

At 200k steps per second...
200000 times 60 seconds = 12,000,000 steps per minute
12,000,000 divided by 16,326.530 = 735 inches per minute (max)

The y-axis inches per minute max is being skewed because it appears to be moving more than what is expected for identical conditions and settings.

You must know the pitch of your screws, than it is easy.

I do, they're 1605 ball screws. The pitch is 5 mm

Finetunning is an other thing, but needs a high resolution dial indicator.

I have a dial indicator that I can use with this.

[suntravel]

Take a close look at the units in the wizard....

turns/in = how many turns are needed for 1 inch

Max rate (inch/min) is limited by the critical rpm of the screw, and by the power the steppers have at speed to turn the screw fast.

1000rpm is eyeballed from experience.

If they stall go slower, if not you can go a little faster, but not beyond the critical rpm the screw starts to vibrate.

Uwe

[fbx]

Take a close look at the units in the wizard....

turns/in = how many turns are needed for 1 inch

Max rate (inch/min) is limited by the critical rpm of the screw, and by the power the steppers have at speed to turn the screw fast.

1000rpm is eyeballed from experience.

If they stall go slower, if not you can go a little faster, but not beyond the critical rpm the screw starts to vibrate.

Uwe

I know both x and z axis are showing at 5.10 and y is at 5.38

I don’t understand why the y-axis moved a noticeably different amount than x and z though, given all axis were a command to move 5 inches. Maybe it’s just the way the math worked out from the spreadsheet calculator. I’ll set them all for 5.08 revs / inch, send each a command to move 5 inches, then measure again to see how close/far off they are.


As for in/min and acceleration, I’ll need to play around with these. I don’t need anything blazing fast - brisk with quick acceleration is fine with me. Do you have any recommendations for in/min and acceleration?