Thermistor wire red hot glowing

fillefrans · 2018-09-23T11:18:39.087Z

Hi everyone, I had problems with the original hotend of my Anet A8 (display showing “def” on temperature), so I decided to try out a Titan/V6 clone. I have got it mounted on the printer, but when I plugged it in, I noticed that one of the thermistor wires was glowing hot, just like a light bulb filament. On closer inspection, I see that the wire is running outside of the sleeve (not sure if it was already like that or if it has melted through). Any ideas what might be the problem, or tips for next steps to figure it out?

thermistor.jpg3161×2394 2.72 MB

4King · 2018-09-23T12:33:42.219Z

Oh man, that look scary, do you think you might have misplug the thermos into the nozzle socket? or maybe have the negative and possible side switch

fillefrans · 2018-09-23T13:06:19.283Z

Agreed, doesn’t look good. The thermistor came already assembled with the hot end, I only got it out after these photos were taken. Is there anything in particular I need to be aware of when putting it back in? I was under the impression that polarity didn’t matter with the thermistor?

MaddieG · 2018-09-24T00:18:08.685Z

Polarity doesn’t matter with most thermistors. Are you showing any error on the screen?

The sheathe should absolutely cover the wiring so if that’s not the case, either it did ship like that and is damaged, or something else is wrong. Oddly, the wires themselves shouldn’t be getting hot enough to melt the sheathing, so if you find evidence that is what occurred, I would switch to a genuine E3D hotend and never look back, personally.