MK3 PID autotune temp too high, fails to run
This is a new MK3 install with Firmware 3.4.0rc1. The hot-end has a silicone sock fitted. In my OctoPrint temp graph I see the temp is over-shooting quite a bit on the hot-end, so I attemped to run M303 E0 S220 C8 multiple times. Each time autotune fails with "temp too high".
autotune ran fine on my MK2S, but fails consistently on the MK3.
What can I do to get PID autotune to run so I can get my hot-end temp to run more evenly?
Re: MK3 PID autotune temp too high, fails to run
After a bit of checking it turns out that the hot-end assembly had a 12v heater cartridge. 12v heater carts measure ~3-4 ohms and 24v carts measure ~12-14 ohms.
I did an online chat with Lukas and he is going to send me the 24v carts (I had ordered two complete MK3 hotend assemblies).
So if your PID autotune fails with "temp too high" measure the resistance of your heater carts to make sure you didn't accidentally get a 12v cart. Also note that if you have a 12v cart in a 24v system the temp will shoot up at an astounding speed. That would be another symptom.
Re: MK3 PID autotune temp too high, fails to run
Same problem here. Just searched google for this odd problem, and ran into your post. I purchased a new assembled e3d hotend from prusa shop and noticed the temperature flux and just now realized it was 12v after your post and many hours debugging.
I also had a powersupply fail during the time I had this cartridge in -- would the flux in temperature have any role in that?