is the Dynomotion controll as confusing as it seems?

[Gunmachinist]

With a Move size of 2000 counts that would indicate the resolution of your system is about 8000 counts/inch.

I think my problem is I'm unsure where to apply these numbers.

Its hard to help when you don't tell us what you did, what happened, and what you understand.
One of the first steps in tuning is to maximize the D Gain.

All of my previous test/findings were with the servos disconnected from the table playing around with numbers attempting to learn what did what. I connected the X axis yesterday to the table and the above screen print was a result of the table connected and a load placed on the X servo motor.

How do I find the start of my Motion Profile Tuning Parameters?
I get that the V Feedforward would be 0.00045 if D gain is 5.
I understand that with the 8000 counts/inch = Measurement size.

[TomKerekes]

I think my problem is I'm unsure where to apply these numbers

Later you will set the resolution in KMotionCNC so that when you command some distance in inches or mm it moves the correct amount. But for now it is to allow us to put the errors and speed into perspective. For example your last plot had errors of about 100 counts. So that is 100/8000 = 0.0125 inches.

All of my previous test/findings were with the servos disconnected from the table playing around with numbers attempting to learn what did what. I connected the X axis yesterday to the table and the above screen print was a result of the table connected and a load placed on the X servo motor.

ok its helpful if you tell us when you make such changes.

How do I find the start of my Motion Profile Tuning Parameters?

Start off making fairly slow moves such as 1 inch per second. This would be 8000 counts/sec

Also at fairly low accelerations. In order to accelerate to that speed in 1/2 second that would be 16000 counts/sec^2

Jerk is not really important at early stages so set it to a large value such as 1000000 counts/sec^3

I get that the V Feedforward would be 0.00045 if D gain is 5.

Correct as a starting point.

I understand that with the 8000 counts/inch = Measurement size.

I don't understand what you mean.

[Gunmachinist]

I don't understand what you mean.

understand that with the 8000 counts/inch = (Measurement size)
If I wanted to make a test move of say 2" then I'd just put 16000 in the Measurement size block, that now has 2000 and only moves .25".

[TomKerekes]

understand that with the 8000 counts/inch = (Measurement size)
If I wanted to make a test move of say 2" then I'd just put 16000 in the Measurement size block, that now has 2000 and only moves .25".

Exactly correct.

[Gunmachinist]

I am having trouble getting my servos to move the machine. I have connected all the axes, removed the tourqe brushes and changed the servo amp to voltage mode to work without the tourqe brushes.

[Al_The_Man]

removed the tourqe brushes and changed the servo amp to voltage mode to work without the tourqe brushes.

You change it to torque mode, not voltage mode if you have removed the tach brushes.
Al.

[Gunmachinist]

You change it to torque mode, not voltage mode if you have removed the tach brushes.
Al.

That may be the problem, I don't have a mode labeled tourqe mode, I changed it from tach mode to voltage mode thinking that was tourqe mode. I have tach, voltage, current and test mode on the servo amp I have.

[TomKerekes]

Current mode should be the same as torque mode. The torque of a motor is proportional to the current.

[Al_The_Man]

If you notice, the settings for the DIP switches is SW1 OFF, SW3 ON for current mode.
The 12A8 is long discontinued model, but you should be able to get them working OK, the loop gain may need adjusting towards max.
Al

[Gunmachinist]

If you notice, the settings for the DIP switches is SW1 OFF, SW3 ON for current mode.
The 12A8 is long discontinued model, but you should be able to get them working OK, the loop gain may need adjusting towards max.
Al

Thanks Yes I changed the switches when I got home and attempted to get an axis moving for about 2 hrs. I was unable to get one to move, the servo tries but acts like it just doesn't have the balls to do it. If I disconnect the belt I get movement. Do I need to change the wiring from the amp pin functions around?

[TomKerekes]

You could diagnose the issue using DAC Commands.

I don't think the wiring would need to be changed.

[Gunmachinist]

You could diagnose the issue using DAC Commands.

I don't think the wiring would need to be changed.

How would I go about doing that?

[TomKerekes]

You could diagnose the issue using DAC Commands.

I don't think the wiring would need to be changed.
How would I go about doing that?

Use DAC commands as you have previously to command Voltages to the Amplifier. Start with small Voltages. 2047 would be full 10V. Check how much torque is generated by the motor. Torque should be proportional to the torque. Reversing the Voltage should reverse the torque.

[Gunmachinist]

I believe I found my problem but don't know exactly how to correct it. I have a power box that is rated for 24v 4a, and my amc servo controllers are 6-12a. If I am controlling 3-4 axis can I add a transformer and capacitor into the system to provide the necessary amps so all axes will run at the same time or do I need a power module that will supply 24v and provide the necessary amps to run all 4 axes at the same time. ?What would be best?

[Al_The_Man]

I have used both, in fact A-M-C sell version each with its own supply built in.
But If you size a mains transformer correctly, one normally does the trick, it is seldom that all three motors are requiring maximum torque at the same time.
4amps seems a little wimpy, even for just one drive.
Al.
.

[Gunmachinist]

I have used both, in fact A-M-C sell version each with its own supply built in.
But If you size a mains transformer correctly, one normally does the trick, it is seldom that all three motors are requiring maximum torque at the same time.
4amps seems a little wimpy, even for just one drive.
Al.
.

Ok, so a 12v 10a power supply should work or do I need more than 10a?

[Al_The_Man]

I thought you were using the PT402 motors?
These are typically found on B.P. mills looks like they are equivalent to the 402CNSPOS72 used on the B.P. also.
I could not find any details on the PT402 except they are rated for 146vdc max.?
But they are a fairly beefy motor so 10a for all servo's would certainly be pushing it.
Al.

[Gunmachinist]

I thought you were using the PT402 motors?
These are typically found on B.P. mills looks like they are equivalent to the 402CNSPOS72 used on the B.P. also.
I could not find any details on the PT402 except they are rated for 146vdc max.?
But they are a fairly beefy motor so 10a for all servo's would certainly be pushing it.
Al.

Yes, those are the servos, run by amc 12a6k servo controllers. So, I need more amps, how would I go about hooking up a compasitor to up the amps when needed?

[Al_The_Man]

The Picture shows a 25A8?
Maximum 80vdc.
If using the PT402 motors ideally you need something with higher voltage rating as the PT402 shows as a 146v max motor.
The 12a8 is 86vdc.
Al.

[Gunmachinist]

The Picture shows a 25A8?
Maximum 80vdc.
If using the PT402 motors ideally you need something with higher voltage rating as the PT402 shows as a 146v max motor.
The 12a8 is 86vdc.
Al.

The sticker on the side of the control says 12a8k. So I need to supply more power, thanks.