Core One crash/restart - Hardware, firmware and software help

RE: Core One crash/restart

Jürgen — Tue, 14 Apr 2026 06:57:47 +0000

Posted by: @simon-warner
What is not clear is whether people are having this problem with pre-assembled or kit printers.

If you read back through this long thread, you will find that the issue has been reported for both, kits and factory-assembled printers.

RE:

Simon Warner — Tue, 14 Apr 2026 06:47:21 +0000

I would like to investigate a little more deeply into this issue: I too experienced the crash / restart issue and indeed cured it by grounding the x/y motors. We can assume from this that the problem is electrical in nature. That much is clear. What is not clear is whether people are having this problem with pre-assembled or kit printers. If the issue is with both variants then it lies clearly lies with Prusa to investigate and rectify. If however the issue is with kit assemblies then that is a different scenario which is not entirely within the control of Prusa - Assuming that it is a problem with kits (purely for the sake of continuing these thoughts) then we should look at what each of us have done differently. I religiously followed the assembly instructions except for one tiny detail. In my case I did not align the axis belt pulleys correctly and as a result one on the belts, unbeknownst to me, was rubbing on the frame. That is a recipe for the generation of static and the subsequent electrical spikes which we assume are the cause of the crash / restart. It sounds very logical to me but what I cannot be sure of is whether the belt rubbing really was the founding cause of the issue. If you simply state that you have had this issue and that you cured it by doing 'xyz'; then it doesn't particularly add to our collective knowledge and the resolution of the actual cause.

RE: Core One crash/restart

Ron S — Mon, 13 Apr 2026 19:11:51 +0000

I have bonded and grounded EVERYTHING and had one crash after. I installed a Transient Voltage Spike diode (33v) across the 24v input to the board from the power supply and so far so good. No crashes yet.

RE: Core One crash/restart

Ron S — Sat, 21 Mar 2026 18:13:57 +0000

RE: Core One crash/restart

Ron S — Sat, 21 Mar 2026 18:11:17 +0000

I now have the X/Y motor shafts grounded. Magnet on top to a ball bearing to a lateral magnet to a screw, to a wire to ground.

RE: Core One crash/restart

Ron S — Thu, 19 Mar 2026 15:11:50 +0000

I have been checking regularly with a Fluke DVOM. All the motors are bonded to ground. However, none of the motor shafts are grounded. They are insulated from the motor housings. So the Z lift screws and the X/Y belt pulleys are wide open. Clearly insulated by the bearings. Been thinking of a grounded ball bearing of some kind to ground the xy shafts from the top. The z lift screws maybe a brush touching the screw.

RE: Core One crash/restart

Jürgen — Thu, 19 Mar 2026 14:08:13 +0000

Hmm... You had mentioned earlier that you did ground the X and Y stepper motors, even before you turned your attention to the heatbed. Could you double-check whether the motors are indeed (still) grounded? Measuring the resistance between one of the four X motor mounting screws and one of the Y motor mounting screws is the quickest way to check.

RE: Core One crash/restart

Ron S — Thu, 19 Mar 2026 13:40:37 +0000

this time it was during a print. It was usually crashing right after

RE: Core One crash/restart

Jürgen — Thu, 19 Mar 2026 12:58:15 +0000

Posted by: @ron-s-2
it either doesn’t matter as it crashed again. Or the static electricity just found a new path.

Under which circumstances did it crash? When you touched the bed, or some other part of the printer? Or on its own, during a print?

RE: Core One crash/restart

Ron S — Thu, 19 Mar 2026 12:57:04 +0000

The new wire I ran through the bed loom to ground the bed assembly did not resolve not resolve the issue