N2 Plus stops suddenly during printing

[Nobbi50]

Hi,
my N2-plus worked witout any problems in the past, but today during a print lasting approximately 23h (out of 33:59 in total for the job) it suddenly stops with "serial error, extruder has stopped". It asked for a retry if I remember well and I did so, but nothing happened. I switched it off and on again after some time of patience. It came up with "we encountered a serial error during last build" and I executed the recover option. I got the message "invalid print file" and pushed "OK" if I remember well. It started to heat up the hotends, but for my amazement the right hotend and very slowly a little the left hotend what rested at approximately 60°C for some minutes. The job before the error was on left hotend only. Suddenly I noticed smoke comeing from the left hotend and I switched off the printer therefore!

I tried again. The smoke came out of the right nozzle when the displayed temperature was 130°C only (seems the temperature was allready much higher?)and now I noticed another mystic behavior: After booting both hotends start to heat up automatically. It is not possible to stop it! The right one heats up to more than the limit of 310°C (I stopped it by switching off at 312°C to avoid damage). The left one is much slower now and I do not know wether it stops at the limit or not due to that. Sometimes I get an error message during boot: !"Error:0: Extruder switched off. Please check hardware and restart".
Can anybody help?

[Vicky@Raise3D]

Should be some hardware problems. Highly likely the extruder board and ribbon cable.

Would recommend to make direct contact with our support team:
help.raise3d.com

[Jetguy]

Right here was a thermal runaway I have warned about.
What happened here is the ribbon cable connection to the extruder breakout was failing in some way. I've warned about this until I'm blue in the face. When that happens, the reported temp remains the same as the last good read. Since the controller board is making decisions on heater ON/OFF based on the reported temp of the hotend, if it's no longer getting a proper real temp report back because the wiring is broken or unplugged, it can lead to thermal runaway (heater stuck on and overheating).

It started to heat up the hotends, but for my amazement the right hotend and very slowly a little the left hotend what rested at approximately 60°C for some minutes. The job before the error was on left hotend only. Suddenly I noticed smoke comeing from the left hotend and I switched off the printer therefore!

Look folks, I don't care if you are new, don't know, didn't read it before, whatever your excuse.
If you own a Raise 3D printer, you need to read this critical safety information I have posted and harped on.
Read this post first viewtopic.php?f=2&t=6580#p26394
You need to order the thermal protector https://www.raise3d.com/pages/thermal-protector-orders
You need to install it https://www.raise3d.com/pages/thermal-p ... structions
viewtopic.php?f=2&p=28305#p28301

[Nobbi50]

I have found the reason: The big connector at the board at the heater was not well fixed. There is for real not a good hooking function between header and cable-connector! I added an extra cable ties to avoid this problem for the future.