How to cut power via smart plug at the end of prints or upon thermal runaway?
Background
I don't have a Core One but a Klipper printer, connected to a smart plug with energy monitoring and home assistant.
In HA I monitor the bed, chamber, nozzle temperature and printer status, so when a print is complete, and once all temperatures drop below a threshold (40 °C), first a "system shutdown" is issues (the Linux mainboard performs shutdown) and then after another delay (1 minute) the power is physically cut via smart plug.
I also monitor the power consumption and if it goes 200 W above what I know it's the actual maximum power consumption, I immediately cut the power because something is going wrong. It's not even via Home Assistant automations, it's in the smart plug itself (I flashed ESPhome on it).
My printer being controlled by Klipper and Moonraker, there is a setting in Moonraker to cut the power of a smart plug upon "klipper shutdown", which typically happens when a thermal runaway is in progress.
So, the printer overall is protected against unexpected total power consumption, and also from thermal runaway of a single heater.
The Core One
A friend bought a Core One so I'd like to replicate these failsafes for him as well.
Overcurrent is identical, hard power cut immediately.
Power cut upon idling and low temperature threshold is similar, but do I need to issue a "system shutdown" before a power cut? does the Core One run a Linux or other operating system which benefits from a software shutdown before power cut?
And what about thermal runaway? is there a way to detect it so I can hard cut the power?
RE: How to cut power via smart plug at the end of prints or upon thermal runaway?
Should I repost in a different section of the forum?
RE: How to cut power via smart plug at the end of prints or upon thermal runaway?
The CoreOne isn't a full general-purpose OS like Linux. You're not going to damage anything by yanking power assuming the printer is idle. There's nothing to shut down, and no storage devices that need to be flushed like a full OS.
For instrumenting this, perhaps using the GPIO "Hackerboard" would be appropriate for sending a signal when the print completes.
RE: How to cut power via smart plug at the end of prints or upon thermal runaway?
The CoreOne isn't a full general-purpose OS like Linux. You're not going to damage anything by yanking power assuming the printer is idle. There's nothing to shut down, and no storage devices that need to be flushed like a full OS.
For instrumenting this, perhaps using the GPIO "Hackerboard" would be appropriate for sending a signal when the print completes.
Thanks, I also did not expect any procedure to be needed for shutting down the printer.
As for the detection of the right moment, I was more thinking about the Prusa Link, since the assumption is that a Home Assistant is in place.
The part for which I had no guesses was the thermal runaway aspect.
It can be caused by failing thermistor, or by a MOSFET/SSR which failed close (as usual) instead of failing open (uncommon).
Thermistor failures are handled in firmware, the power is simply cut.
If there a failure of a MOSFET/SSR something further upstream has to cut the power. How to detect a thermal runaway to take care of this failure mode?
RE:
As stated before - you can force power off Core One with smart socket. There is one caveat - just make sure to wait until nozzle temperature is below 50C ( or the fan on the nozzle stops blowing). This is to prevent heat to creep up to the higher areas - normally you want the printer to cool down and shut down. Only in emergency kill the power - you are risking having printer part failure vs major fire hazard.
You can access printer status via PrusaLink embedded in the firmware, so you can fetch data via web with basic auth, and thus you can use esphome directly ( but a bit cumbersome).
Or you can integrate it with Home Assistant - which helps to add additional automations, and much easier esphome integration.
If the printer has issue with mosfets then it will go to error state, ir if the fuse blows it should just auto shut down itself.
See my signature for more ( github 3d-print repo).
See my GitHub and printables.com for some 3d stuff that you may like.