MCU Shutdown when plugged into USB, PSU Overload

General Discussion
1

Basic Information:

Printer Model: Anycubic Kossel Linear Plus
MCU / Printerboard: Trigorilla 1.1
klippy.log

Describe your issue:

I let a print run while I was at work, and when I came home the print had finished but I had a “Lost communication with MCU” message. Restarting the firmware didn’t change anything. I turned off the PSU and restarted firmware. That worked. On closer inspection, the PSU was in Hiccup Mode. A little digging on the Klipper FAQ revealed this:

“Make sure the printer’s power supply is not being overloaded. (Power fluctuations to the micro-controller’s USB chip may result in resets of that chip.)” Source

I believe this is the issue, but I’m not sure where to go from here.

Update: Tried new USB cable. No luck

…
klippy.log (44.0 KB)

2

If everything was fine up to then, it seems the PSU died.
The only adequate solution is to get a new PSU.

3

That’s what I was afraid of. I did notice something else however. When Disconnected from USB, the PSU works fine. No hiccup mode. As soon as I plug it in to USB it overloads.

Could that be a controller board issue then?

4

Could be some kind of backpowering issue: Power goes from the printer to the device on the other end of the USB cord.

What is it that you have connected there?

You may check this:

5

One question, where is the jumper sitting?

1000×1000 187 KB

Good luck, hcet14

1 Like
6

It is currently plugged into a PC running Linux Mint

I gave this a shot.

First covered the + rail. It had no real affect.

Next covered the - rail. This prevented overload for a few seconds until it finally failed.

I noticed the cable got extremely hot during that time.

7

I’ve tried both positions with no change in result.

If the usb is plugged in… overload.

Maybe its the board itself? It almost seems like the PSU is shorting to the casing of the USB… im not sure if that’s possible or what could cause that :sweat_smile:

8

A sign for overcurrent.

Tried a different cable? A different USB port at the PC?

9

So I tried a few different cables and ports. Two front panel USBs and one rear IO. No luck.

However, I did test with a secondary MeanWell PSU that a friend loaned me. Its wattage rating was much lower however (15W instead of my 350W). Plugged it into the USB while powered via the smaller PSU and no overload!

So, I guess that means that the issue is a faulty power supply.

Although, the current running through the cable like that is a bit concerning.

Thank you all for your input in trying to troubleshoot this!

10

for best result, use a separate 5v, 3 or 4 amp power supply just for rpi (connected directly to the 5v and gnd pin on the gpio port)

connect the rpi and the motherboard to the uart rx/tx pin! , do not use USB if possible

check the gnd wire in the power supply, the negative output of the all power supply must be connected to ground! , otherwise that poses the problem in question!

and if you absolutely want to use usb, isolate the +5v wire! (strip or cable modify/diy) check our configuration on your motherboard for the 5V dc rail and not the usb!

11

What rpi?

The OP runs a PC with Linux on it.

12

ho sorry , i read too quickly :slight_smile:

in this case , just isolate +5v usb cable :slight_smile:

but is possible cause is ground loop computer/mcu ! check this , powering pc , and printer , usb not connected

just pick up usb cable and touch the gnd computer part (chassis) to gnd usb cable ( blindage ) , not connect just touch , in dark room ! if arc is produce GND loop problem , cause , negative output of supply ,not connected to ground ,and or bad ground home installation !

risk of electrical shock , caution !

13

That one shuts immediately down in case of a short circuit

If you really get that hot USB cord, there is a short circuit and a new PSU would not help at all.

14

That was my thought as well. Why would changing the PSU make a difference?

So would that mean I need to check grounding and put tape over the 5+ rail on the USB cable as @maddoc suggested?

15

It’s about backpowering as I explained in post #4

To prevent this, there is the jumper @hcet14 mentioned in his post.

16

That makes sense. I did try adjusting the jumper as recommended but still had the overload issue. I’ll try checking my grounding and applying the suggested solutions again to see if there’s any luck!

17

Might make sense, but take real care!!!

Alternatively use a multimeter and measure that “maybe existing” potential!

You could measure the potential with both jumper settings.

If you are unsure, what to do ask here again.

1 Like
18

yes of course, if you have a correct voltage tester, you can test in 240Vac mode then if nothing is measured, in 300Vdc, if it is AC you have a problem with the electrical installation of your house, if it’s DC you have a problem with the printer power supply or the PC power supply

please be careful with leakage voltage, AC or DC!

19

I don’t understand, what you said. What device are you using to measure the voltages (potentials)?

20

current/tension tester :slight_smile:

8-en-1-stylo-Testeur-de-Tension-electrique-0–380-V-Maroc
8-en-1-stylo-Testeur-de-Tension-electrique-0–380-V-Maroc1300×1248 99.3 KB

sorry , i am Belgian , not sure to good word for this :slight_smile: