Hot End Causing Arduino Reboot

Hello everyone,
The past couple of weeks I've been having an issue with my RepRap Prusa i3. While heating up the hot end the Arduino reboots. The printer is a kit from RepRapGuru that I put together about a year ago, and have been printing with almost daily since. If I shut down power for a while I can heat up the bed and the hot end and print just fine. But (usually) after one long print trying to bring the hot end to temperature causes a reboot. Bringing the bed to temperature does not cause a reboot, nor does running the mapping for a BLTouch (which uses all the motors except the feed motor). I've replaced the Arduino (now using a genuine made-in-Italy board), the RAMPS board (v. 1.6 now I think) and the power supply. I've also put separate power to the Arduino and tried printing from the SD card -- same result. I've got a new heater+thermistor on order but the Ohm meter says they are fine. I'm about at my wits end here, it keeps happening and nothing seems to be wrong. Does anyone have any insight or suggestions? There are chickens next door I *could* sacrifice if that would help..... Thanks for any input

Dan

Hi,
have you tried PID tuning for the hotend?
A bad PID setting usually causes thermal_runaway error message or similar, but it won't hurt to try and see if the reboot still comes.
Also looking for the right Marlin version can help. ( latest != best )

My controller was rebooting all the time and tried everything to fix. As I have two identical 3D printers and only one was rebooting I eventually ruled out the configuration.
Finally call the manufacture explained the problem they suggested a replacement controller, this was the solution to my controller rebooting at the end of hours long perfect print.

Have been meaning to further test the controller that was replaced though never have the time or a spare 3D printer to use to test it with.
( Maybe this Winter! )

Not saying this is your problem just putting out information for you to examine.

Edited 1 time(s). Last edit at 07/23/2018 07:29AM by Roberts_Clif.

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Computer Programmer / Electronics Technician

I had not looked at PID tuning, I've been mostly focused on the hardware as it seemed like there might be a current spike causing a brown out. Thank you for the pointer, I'll have to dig into that thoroughly. The firmware I don't think is the problem. I upgraded to v.4 from v.2 because I needed it to control a BL Touch, but I did so in January, long before this problem started.

Thank you. I presume you mean the LCD controller. I did try running once without it and had the same problem, so I reattached it and hadn't really looked at it any more. I will look into that more closely.

I finally figured out what the problem was, so I'm putting it here just in case someone else has a similar problem. The problem was that the heater had infinite resistance *AFTER* working fine for an entire print. Letting it sit for a few hours seemed to correct whatever the trouble was. I'm not sure quite how this works, though I'm sure there's an EE here that could explain it to me. When I tried to heat up the hot end, it would fail, with a message from the firmware -- "Heating failed. Please Reset" . The Repetier host/server software would see this message and reboot the Arduino and flag it in a message that said "Firmware was halted". So the reboots had nothing to do with the problem. I found that letting the heater cool off enough to touch and then jiggling it in the hot end seemed to work, and pulling it out, re-seating it and snugging down the screw seems to have fixed the trouble. But I'm still going to replace the heater & thermistor just to be on the safe side. Just as soon as this print finishes. I swear Thanks @Roberts_Clif and @o_lampe for the good suggestions. They led me to the problem.