Bed Thermal Runaway while Attempting Bed PID Autotune
Hey all,
So today while printing a nozzle torque wrench I experienced a bed thermal runaway error on one of my machines. It has grown colder outside and my ambient temperature inside has dropped some but it's not real cold. I realized I was printing a small part in the center of the bed and using the part cooling fan. So I moved the part and I was able to print it ok.
So I thought I might attempt to calibrate the bed,as it is a bit colder, and I am printing some ABS over the coming months and need the higher bed heat.
So I decided to try the procedure I found here:
I sent this to the printer:
M303 E-1 S100 C8
It say it's starting Autotune and goes for about a minute and gives me a head bed thermal runaway error. The bed temp stays right around 100c +/- 2-3 degree when this happens... Has something changed? Am I doing some thing wrong? Cooling fan was off during this as well. Possible hardware issue or normal?
I can print with the bed at 100 no problem as long as I watch the part location and cooling fan speed.....
Thoughts?
Thank you!
Chad
Re: Bed Thermal Runaway while Attempting Bed PID Autotune
I checked the connection at the Rambo and felt it for heat. All seems normal here. I've been printing parts at the bed center for two months since I got this machine with no problems. Up until today I've only been using bed temps around 55 to 65c. I'm going to check the power supply voltage next, but I'm really most curious as why the PID Autotune is failing.....
Re: Bed Thermal Runaway while Attempting Bed PID Autotune
So i just ran this procedure on my 2nd machine, It worked perfectly. Not sure what is going on here. the only difference is the problem machine is running the latest firmware 3.10 and the machine that this is sucessful on, is running the older 3.0.10
So i am guessing there is a fault in the other machine or a firmware issue.....
Solved? Re: Bed Thermal Runaway while Attempting Bed PID Autotune
Ok. Potentially solved, I did two things.
Upped the voltage in my psu to about 12.9v from 12.08v, and I ran the PID Autotune again differently:
Started the tune at 55C first to see if any issue, Success. Saved values,
Then I tuned again at 70c. I noticed here that my temps seemed to be more stable. Success, saved values.
And then tuned again to 100c, and again I had success. Saved.
Best,
Chad