[bhurts]

When you switched power supplies did you remove the jumper on k-flop for usb power? What does your snapamp initialization look like? How many amps and volts are you limiting to?

Ben

[JakeHappiness]

Hi Ben,

Yes, I did remove the jumper.

A few posts down are all my init files.

I removed the voltage clamp. It didnt seem to have any effect.

Amps are set by the microstepper amplitude to 239 or about 8.2 amps.

Thanks for looking!

Jake

[bhurts]

If you haven't set your snapamps in c like shown at the bottom of the snapamp use and settings help file it might be worth a try. I do not use steppers but I thought that had to be set for proper initialization of snapamp. I may be wrong though.

Ben

[JakeHappiness]

Hi Ben,

The end of my init programs do include the Peak_Current_Limit. I think that is the only one required. It is an intermittent problem. At times it all acts smooth as glass.

Jake

[bhurts]

I'm stumped. I looked at your c programs and didn't see anything that jumps out at me. Sorry I can't be more help. The only other thing I can think of is did you flask new version when you moved to 433k? I'm am not trying to insult your intelligence I just know I missed doing it on a upgrade once.

Ben

[JakeHappiness]

Hi Ben,

Thanks for looking.

I did do the flash. (No insults taken!!! only appreciation.)

It is an intermittent problem. Tom, thinks it must be interference. I keep chasing it. Going to put a scope on DC supplies today.

Thanks,

Jake

[TomKerekes]

Hi Jake,

I did find a few issues with your code.

Level 9 for Peak Current on SnapAmp is nearly zero. Even though you are not using SideB of SnapAmp #1 it may be triggering and faulting both sides (Z Axis). Try setting to level 10 or 11 like side A.

WriteSnapAmp(SNAP1+SNAP_PEAK_CUR_LIMIT1,9);



The homing routine is setting the SoftLimits for Z incorrectly. I believe your Z range is negative so it should be -1250

// restore limit settings
ch4->SoftLimitPos=0;
ch4->SoftLimitNeg=1250;



The Initialize Z only has an error of Axis 41 instead of Axis 4. This may cause unpredictable results until after KFLOP is re-booted and KMotionCNC is restarted.

DefineCoordSystem(-1,-1,41,-1);


Regarding noise and Grounding: Grounding is very complex. Its hard to understand how your system is wired, but from your description it sounds like you have many Grounds and Earth Grounds. This can sometimes be a very bad thing as it forms ground loops and couples noisy earth Ground int Logic Grounds.

With regard to limit wiring noise. You might try disabling limits temporarily for your Axes to isolate that as an issue. Then after everything is working perfectly try adding them back in.

Sorry you are having all these problems. These issues probably don't explain all the weird behavior but probably add to the confusion.

Regards

[JakeHappiness]

Hi Tom,

i fixed those code things.

Thanks, I like clean code. Didn't help though.

So here are results from another experiment you recommended.

Disconnected SnapAmp#A (SnapAmp#A is the one that you looked at for repair but did not find any issues.)

SnapAmp#B Hooked to X,Y (CH0,CH2)axis. all functioned perfectly. I could not get any trouble to happen at all.
(one caviat. . .until I set CH4->output0=0 and CH4-output1=0 CH4 on axis graph showed full RED.)

Switched connector to Z motor and changed CH4 to use ou\tput bits 8,9 and set CH0 output bits to 0
Z axis worked perfectly. Initialized, homed. All smoth.

Switch to SnapAmp#B taking care to switch jumper, inputs . .

X, Y on Channels 0, 2 worked perfectly again. (again if CH4 output bits were still on 8,9 it would show full red bar)
Switch motor connectors so only Z axis is connected.

This time, Analog screen did not reflect the voltage of the supply. I measured voltage at the pins at 60V. Clearly nothing would move.

So I switched wiring to other side and set CH4 to outputbit 11,12.
Worked perfectly!

Put both snap amps on line with Z on output bits 13,14.

CH0,2 work perfectly, CH4 struggles making a little of that Dunk Dunk Dunk noise.as if it doesn't have full juice but eventually makes it through full homing routine without overloading anything..

I think it is the snapamp board. What do you think? Any chance you can send me another SnapAmp to swap?
I am desperate for this machine to be working.

Should I just order another one? I don't have another two weeks for the boards to make a round trip to you.

Thanks for your help,

Jake

[TomKerekes]

Hi Jake,

I'm thinking I know what is going on. There are two Motor power GND connections on SnapAmp JP1. One for each "side" of SnapAmp. They are normally connected together internally in SnapAmp. I believe when you applied motor power to one side backwards you blew the internal connection in SnapAmp as you were applying Motor Power + to one GND Terminal and Motor Power - to the other GND terminal. We didn't catch this when we tested the board. Although we tested various voltages applied to both/each side we never removed our GND connections from both sides. You should be able to verify this by disconnecting all power and connectors and continuity checking between the two GNDs on SnapAmp JP1. There should also be continuity between each GND and the corresponding negative terminal of the big Capacitors.

So using the Side A or B should probably work correctly as long as Motor Power GND is applied to both sides of SnapAmp.

During the Test of Z on side B of SnapAmp #1 did you remember to increase the Peak Current Limit Setting to level 11? Of not that would explain the "Dunk Dunk Dunk" peak current faulting.

HTH
Regards

[JakeHappiness]

Tom,

Grounds are indeed disconnected internally.
I installed a jumper to the other one. It might have helped a bit, but the problem still keeps happening.

Unfortunately, I did have the current limit at 11.

Jake

[TomKerekes]

Hi Jake,

Is the problem still the "Dunk Dunk Dunk" sound? I'm assuming that is the Peak Current Faulting and re-activating about every 1/2 second. Is the fault light on SnapAmp blinking in sync with the sound?

Instead of Homing you might do a move on the Step Response Screen to see if you can capture what exactly is happening. If you are able to post the data file so we can plot what and however we want to try to understand it.

But it does seem like the SnapAmp has been damaged beyond repair.

Regards

[JakeHappiness]

Hi Tom,

The Dunk Dunk Dunk, is a problem in that the stepper definitely looses count.

Typically though as soon as that behavior starts, the other axis go into overload. Most times after that,. the axis that went into overload will be dead until the KFLOP is reset.

Occasionally the Z will go into overload and then the X, Y will still jog fine, but will be Very rough.

Just a data point for you. The trouble started with putting 100V on the motor input pins, not reverse voltage.

So I will just order a new SnapAmp. Is the damaged one of use to you for trouble shooting for the future or anything?

Thanks,

Jake

[JakeHappiness]

Tom,

Thanks!!

I really do like your stuff a lot.

My company is a 1.1 person company.

Happy day,

Jake

[JakeHappiness]

Hi tom,

New Snap Amp installed.

System is noticeably more stable. However, My Z axis still sometimes goes into the overload condition during homing. (it never does it while jogging go figure. . .)

So I am concluding that my Z motor must be bad. Do you concur?

Thanks,

Jake

[TomKerekes]

Hi Jake,

No I don't follow your logic. If the Motor Jogs ok that would indicate a good motor.

Not sure I know what you mean by "overload". Do you mean peak current limit faults? (fault LED on SnapAmp flashes on?)

Or is it simple a Stepper Motor Stall. It might be a mechanical resonance at that speed. How is your motor coupled to the load?

Is the Home C Program you posted a while back still current? It seems to move positive at 50 cycles/sec? You might try to perform a similar Velocity move using the Step Response Screen to see if you can capture the event. That should clearly show what is happening. If so save and post the raw data.

Regards

[JakeHappiness]

Hi Tom,

I am happy to report much improvement on a few fronts.

The major issue is solved. As you have suggested several times while helping, the issue was interference. By chance I had the radio on really loud so that I could hear it over the rotary phase converter and fans. I could hear in the static the same bad behavior that I could Se on the axis current graph as the axis went into "overload."

So I have continuous metal covers separating all AC / DC / signal / power, and it did help some somehow. Sometimes it would recover from the "overload" condition by itself after a few seconds.

I got to thinking about the motor power grounds being connected together on the two sides of the snap amp and realized that on the inside of the power supply that supplies the three motors, (One one each output phase of a 3-phase transformer) the grounds were also tied together as they had been with the original drive setup from the 70's. Separating these very cleanly the machine is running great!

I ran the homing program about 50 times both through the C window and through the KmotionCNC with only one issue. I had stopped to mess with the code to make it repeat the homing for a while. A typo caused it to hit the top Mechanical Limit. The machine has good overload clutches so it didnt mind too much, but the SnapAmp axis did its "overload" thing. Visually the current graph goes red and stays there, regardless of disabling axis, all axis, reinitializing . . .only Resetting the KFLOP will allow it to resume normal operation. When it is in the bad state the other two axis still work, but run roughly. . .

I did order one new motor in the process, so I will see if that has any effect too.

Thoughts?

Happy day and thanks for your help.

Jake

[TomKerekes]

HI Jake,

It sounds like you had a major ground loop situation with your power supplies. So I suspect isolating the grounds is what helped.

I don't understand the "overload" thing. Seems like a huge current draw triggers the problem. I assume the high current reading remain even with the motor supplies turned off? Please post a screen shot of the Analog Screens (both SnapAmps) if this occurs again.

Regards

[JakeHappiness]

Tom,

I believe that I still have interference problems. I have shielded cable to run between motors and SnapAmps on the way. Currently they run from all motors in a bundle with no shielding. This should help.

It is improved enough to make some real progress though. It homes all three axis nicely 9 out of 10 times. I have run a few basic programs in g-code in KMOTION CNC.

So now I am trying to get Mach3 going. I have the general config good. I can jog, I can do basic G-Code. It sees the Opto Inputs on the SnapAmp for limit switches and E-Stop.

Cant get any of the Ref buttons to initiate homing. I transferred the guts of my good homing program into the frame of the provided HomeMach3.c Nothing happens from either the Ref All button or the RefX, RefY, RefZ buttons on the diagnostic screen. Any ideas?

thanks,

Jake

[JakeHappiness]

on the Mach3 homing i FOUND THIS

Hi Slimneil,

. . .
Mach3 has a quirk if Homing Inputs are enabled in Mach3 | Config | Ports and Pins | Input Signals | X Home, Y Home, Z Home, A Home, B Home, C Home then Mach 3 will NOT call the Plugin to do Homing. Please make sure these Inputs are NOT enabled. KFLOP performs the Homing operation not Mach3 so Mach3 doesn't need to know anything about which inputs are used.


HTH
Regards

That part is good.

Thanks,

Jake

[JakeHappiness]

Hi Tom,

So after finding the ground loop problem, interference was vastly reduced, but still did the overcurrent thing.

So I replaced all motor cables with shielded 5 conductor cables. Shield tied to power supply ground, 5th conductor tied only to motor housing.

I have not had a single motor overload issue since!!

When I hit a mechanical limit one time I had to reset klop. Fair enough!


I have Mach3 running
-Should I use KFLOP motor limits (hard and/or soft) while using Mach3?

-a few weird issues.

-Continuous jog works nicely in all axes. When I try to step jog, I get really rough movement and then mach3 must be e-stopped and reset before it will do anything again. (IKFLOP not reset and KFLOP shows no issues). dynoCNC does all perfectly (of course)

Any idea?

Also when I hit the Goto Zero button, Mach3 goes into the same do nothing mode after a small bit of movement toward zero.

Any ideas?

Thanks!

Jake