Dead PanelDue 7I

A Former User

I am a great fan of this product line, but on other printers I can move the head back and forth, and not kill parts of the printer.

Is generally ill advised; weather or not its a problem depends on protection of the board (don't think you can beat the Duet on that, unsure about the PanelDue) and possibly more relevant, the speed of which you move the motors while connected to the board.

I'd say if you light up LEDs etc, then you would be better off disconnecting the motors first.

Danal

@MikeD said in Dead PanelDue 7I:

I am also fairly certain it is dead, but want to be sure I am not missing out on anything.

Next question of course would be is this covered under warranty ?
I have already ordered a replacement, even if I can recover this one somehow I can use it on another project.
I am a great fan of this product line, but on other printers I can move the head back and forth, and not kill parts of the printer.

I have absolutely no hard facts, gut feel only, but I'd be very, very surprised if moving the motors caused the Panel Failure. At the same time, I am not a big believer in coincidence, so I don't really now what to think.

None of which helps you with your dead board...

MikeD

Is there a more "official" place for me to ask these questions ?
Would the next step be to contact Filastruder where I purchased it from ?
Or sit and wait until someone reads this post ?

A Former User

Filastruder would likely ask you to come here to have any warranty claim evaluated by dc42, T3P3Tony or possibly droftarts(?), so I guess yeah, wait for one of those to do that.

droftarts

@MikeD Sorry, I'm a bit late to the discussion. We're just discussing this amongst ourselves. All I can say at the moment is that I've destroyed a RAMPS board in the past, by moving the motors. They effectively act like generators, and the voltage can escape the stepper driver and cause all manner of problems, depending on the voltage (proportional to speed the stepper is moved) produced. I don't know if there is protection in the stepper drivers, or on the Duet, for this.

The other think is that leaving the PanelDue for a while (eg 24 hours) may make it come back. I'd try it again after a reasonable amount of time, and see if it works. You can replace the PCB, but then it may be the display or backlight that has failed!

Your PanelDue is within the warranty period, but I'm not sure if this would count as a warranty replacement. We're just discussing that.

Ian

MikeD

Thank you for the response.
A lesson has been learned for sure.
I have read a great deal of the documentation dealing with the Duet and Wifi Board even before I purchased one, I was aware of many things not to do like plug and unplug motors under power, even remember reading the How to destroy your duet 2 article. I never saw anything warning against moving motors plugged in.
It does seem like that is something many take as a common sense thing, and it will be for me also in the future.
My only other piece of hardware is a CR10S pro, that seems to be completely immune to backfeed damage, so perhaps stupidly I was not cautious enough.

Filastruder has already denied warranty, I am not quite so sure how I feel about it. I can agree that my actions may have caused the damage, just not so sure they should have.

Barring any warranty replacement, is there a repair service offered ?
If not, any tips for what to look for to replace, single component wise off the board. I am assuming (hoping really) a backfeed voltage spike would damage a single surface mount component such as a diode or capacitor, i have a reflow station and other tools required for that type of repair.

I realize that it may be hard to diagnose what it is that failed, but lets say if I commit to spending up to half the cost of a new PanelDue dollars and a few hours of work, what would be the first things one should look at replacing ?

Mike

A Former User

@MikeD said in Dead PanelDue 7I:

I realize that it may be hard to diagnose what it is that failed, but lets say if I commit to spending up to half the cost of a new PanelDue dollars and a few hours of work, what would be the first things one should look at replacing ?

Mike

hard to give a good written guide; but as you've already determined you cannot reprogram the board which suggest there is a problem with the atsam mcu. I'd first check the onboard 3.3v regulator, if its okay then replace the mcu.

having done that you could still have issues with the lcd panel, so not easy to evaluate if worth while.

edit: cant recall having seen the 7i schematic, but the regular v3 is close enough for the bits above
https://github.com/dc42/PanelDue/raw/master/PCB/V3.0/PaneDue-3.0-schematic.png

Phaedrux

That's a tough lesson. Sorry about that. It should be fairly well known that motors are generators when driven in reverse. You saw lights coming on after all. I've seen numerous warnings to not move the motors quickly if you have to move them by hand.

Perhaps the hint to the failure lies here:
https://duet3d.dozuki.com/Wiki/How_to_destroy_your_Duet_2#Section_Methods_that_are_very_likely_to_write_off_your_Duet

excessive voltage on the 3.3V rail will back-feed into the 5V rail too, so you will destroy even more chips, and with luck the backlight inverter on your TFT panel too if you have one.

The article is a bit tongue in cheek.

At least the board itself is still functional.

Phaedrux

https://duet3d.dozuki.com/Wiki/Warnings

Point #4

When the stepper motors are connected to the Duet, do not move any parts by hand that make the motors rotate rapidly! For example, if you need to move the print head by hand, or the carriages of a delta printer by hand, do it s-l-o-w-l-y. Likewise, if you need to rotate the extruder gear by hand, do it slowly. Rapid rotation of the stepper drivers will generate enough voltage to power them up in an uncontrolled fashion, and could generate enough to exceed their rated voltage.

A Former User

@Phaedrux said in Dead PanelDue 7I:

The article is a bit tongue in cheek.

the accompanying youtube video was my first encounter with anything duet3d, (incorrectly?) assumed it was some random nutjob doing a parody ... but I have since been enlightened:)

Phaedrux

@bearer said in Dead PanelDue 7I:

random nutjob

Nope, it was a very specific nutjob.

MikeD

Yeah, should have known better, will know better.
Anyways, moving on ...
I am not at the board at the moment, but I do remember it has some exposed copper pads that I assume are test points. Any of those for the 3.3V ?
What would be the easiest way to test for a blown 3.3V regulator ?

A Former User

@MikeD said in Dead PanelDue 7I:

I am not at the board at the moment, but I do remember it has some exposed copper pads that I assume are test points. Any of those for the 3.3V ?
What would be the easiest way to test for a blown 3.3V regulator ?

not sure about the test points as I haven't seen the schematic for the board.

measure resistance across input and outputs (without power applied), feel if it gets hot, measure the output voltage, look at the output with a scope, in increasing order of ease/reliability of the test.

droftarts

@MikeD this from @T3P3Tony :

It's possible to generate quite high voltages and backfeed them if the motors are spin manually. They become generators and the voltage is related to the rotation speed. Often this is a particular issue where gearing is involved as moving the axis s
Relatively slowly can lead to the motors spinning rapidly.

Now saying that does not directly releate to PanelDue damage unless the generated voltage caused the 5v regulator to fail shorted.

So check the Duet too.

Ian

A Former User

Verified that the Duet Wifi board is outputting 4.98 volts to the panel.

he did

Danal

If you get to the point you can make no further progress with the dead Panel assembly, there are several of us that have volunteered to look at repairs, WITH NO GUARANTEE beyond that we will send your board back worse off than we received it...! All kidding aside, we can at least try.

If you decide to pursue that, search for "repair" and you'll find a thread with a couple of people. I am one, I'm in North Texas USA from a shipping cost perspective. I am an amateur/hobbyist... but I do have hot air rework, O-Scopes, soldering reflow ovens (settable to certified profiles, even), etc, etc.

Let us know...

MikeD

@Danal

I am definitely interested.
Short of waiting for the fairy to make it all better I am out of recourses. I have been able to verify that at least one regulator is supplying 3.3 volts, there is another one furthers stepping it down to 1.something. But that's about it.

A Former User

@MikeD said in Dead PanelDue 7I:

I have been able to verify that at least one regulator is supplying 3.3 volts, there is another one furthers stepping it down to 1.something. But that's about it.

The micocontroller that is refusing to give you a serial port only needs 3.3v. 1.8v would be for the lcd controller but would need a working microcontroller to evaluate it if also needs fixing.

MikeD

@bearer

Yeah, based on not much more than a gut feeling I think it is going to be one of the micro controllers on the board.

dc42

If the PanelDue won't show up as the Bossa port after you have done all the usual things, then it sounds that either the ATSAM4S4B processor has failed, or the USB port isn't making contact, or there is no +3.3V supply to the ATSAM processor.

The 3.3V supply comes from U4. There should be +3.3V on the end of CA9 closest to the ATSAM processor UA1. The case of the SD card socket can be used as ground when measuring this. There should be 1.2V on LA2. The ATSAM should not be getting hot.

The flashing from the display sounds odd, almost as though the backlight inverter has failed or there is a poor power contact. Are you sure that the backlight is on continuously? Even with the screen dark, I can see it at the edge of the display where the Kapton cables come out of it.