How To Test Thermal Runaway Protection...Safely!

hello 3d printing friends today on the BB 3d channel we're going to cover safe ways to test the thermal runaway protection feature on 3d printers stick around and we'll get into it right after this I'm Brian and you are watching bv 3d hi welcome back hey if you're new here and you're wanting to learn about cool 3d printer upgrades 3d modeling and other 3d printing related stuff start now by subscribing and clicking the bell so you don't miss anything ok so today we're going to see how to test the thermal runaway protection feature of a 3d printer safely now why test thermal runaway protection well the short answer is safety this feature can help prevent 3d printer fires now let's talk a bit about thermal safety features available on 3d printers the printer uses or misters to measure temperature they're misters are thermally variable resistors electronic components whose resistance varies as a function of their temperature so by reading the resistance value the printer can determine the temperature of a thermistor typically the printer has a thermistor in the heater block on the hot end and if it has a heated bed there's one attached to the bed now there are two kinds of thermal errors there's a min temp error and a thermal runaway error a min temp error is part of a basic test to see if the thermistor is even connected so if a thermistor has failed in such a way that it doesn't return a value at all or it's been unplugged from the main board or it's cable has a break in it you will see a min temp error a thermal runaway error is one in which the printer is trying to get one of its heating elements to a desired setpoint but it fails a setpoint is the target temperature that it wants to reach or maintain and it's either set in g-code when you're printing a file or you can set it from the printers control panel such as when you're trying to unload or look filament or preheat the printer for printing so imagine this scenario the small screw securing the thermistor to the heater block at the nozzle has come unscrewed and that there mister is no longer being held in place in the heater block it can't accurately report the temperature of the heater block it can only report the temperature of the air in the room now the printer wants the heater block for the nozzle to be at 200 degrees C and the printer reads the thermistor NC is the ambient room temperature say 23 degrees C so the printer applies power to the heater cartridge and monitors the temperature reported by the thermistor the printer doesn't see the temperature of the heater block it only sees the ambient room temperature without thermal runaway protection enabled printer will continue applying power to the heater cartridge and it is not going to stop until that thermistor reads 200 degrees C now meanwhile the heater cartridge is going way past that temperature but the printer doesn't know that it sees room temperature but it wants to get to 200 degrees C come hell or high water and it is not going to give up trying so it keeps applying power to the heater cartridge now meanwhile there's smoke pouring out of the hot end as whatever filament was in it has cooked off and if there are any other plastic parts near it they can start to melt or even catch fire but with thermal runaway protection enabled while the printer is applying power to the heater cartridge if the temperature doesn't start moving toward the setpoint or doesn't move toward it fast enough the printer knows something is wrong it will declare a thermal runaway condition and it will stop everything it's doing which also means it'll cut power to the heater cartridge and at that point you'll need to reset the printer by removing and reapplying power now thermal runaway protection doesn't just work at the beginning of a print job when the printer is trying to get up to temperature that feature is constantly monitoring the heating elements temperatures so if the thermistor gets pulled out of the hot end because a screw fell out and it's cable snagged on a curled up part of a print the printer detects that drop in temperature and sees that it can't keep the temperature at the setpoint so again after a few moments the printer shuts down with a thermal runaway error so how can you test your printer to see if it has thermal runaway protection enabled well there are a couple of unsafe ways to test it one is to remove the heater cartridge from the hot end and then set the temperature to 200 degrees C and watch to see whether the heater cartridge starts glowing red hot or whether the printer shuts down another one is similar remove the thermistor from the heater block at the hot end and again set the temperature to 200 degrees C now you won't be able to see if the heater cartridge is glowing but you can monitor the hot end to see if it starts smoking or if the printer shuts down but we're not going to do either one of those we do not want to summon the fire gods now there are a couple of safer less smoke-filled ways that we can test this feature that don't involve things getting fire starting ly hot one of them is super easy the other involves getting inside your we'll start with the easy way first I call this one the USB power method if your printers mainboard can be powered by its USB port you can use this method to test your printer and here's how to find out if you can use this testing method plug in a USB power adapter such as a cell phone power adapter and turn the printer off connect a USB cable from that power adapter to the printers USB port if the screen lights up and the printer boots you can use this method so having determined that you can use this testing method here's how to actually perform the test with the printers power switch turned off and a USB power adapter providing power to the mainboard set the nozzle to 200 degrees C since the USB port can't provide enough power to move the stepper motors or operate the heaters the nozzle temperature will remain at room temperature this simulates the thermistor or heater cartridge being pulled out of the hot end if this actually happened on a printer the thermistor would no longer be able to provide the mainboard with an accurate temperature reading and without thermal runaway protection enabled the printer would keep the heater powered on trying to reach that to at a degree set point but if thermal runaway protection is enabled once a short amount of time has elapsed without the temperature moving toward the setpoint their printer will display a thermal protection error and shut down requiring a reset now if several minutes go by and the printer still hasn't complained or shut down the most likely reason is that the printer doesn't have thermal runaway protection enabled now if your printers mainboard cannot be powered by its USB port there is another safe way to test the thermal runaway feature which I call the unplug the heater cartridge method now if you're not comfortable opening your printer loosening screw terminals unplugging things and then putting everything back together again do not do this if you are though here's how to do it oh and you're doing this at your own risk if something goes wrong and you break your printer you've been warned okay so first turn off the printer then access the printers main board now usually this involves removing a couple of screws and then removing a metal panel covering the printers innards the exact placement of wires for the heater cartridge varies by print typically what you're looking for is a pair of heavy-duty wires connected to screw terminals on most main boards you'll have three pairs of these one pair is the power input for the board coming from the power supply one pair is the power output for the heated bed and one pair is the power output for the heater cartridge for the nozzle using this reality board as an example the power supply connects here the bed connects here and the heater cartridge connects here now again the placement varies by printer so it's on you to figure out which pair of wires is powering the heater cartridge so loosen the screws securing the heater cartridges wires in the terminal block and then remove them if you want to be extra careful with them you can wrap the ends in electrical tape so that they don't short out against anything else inside the printer with those wires disconnected turn the printer on and set the nozzle to 200 degrees C after a short amount of time is elapsed without the temperature moving toward the set point if thermal runaway protection is enabled the printer will display a thermal protection error and shut down requiring a reset however if several minutes have gone by and the printer still hasn't complained or shut down well again the most likely reason is if the printer doesn't have thermal runaway protection enabled so with the test completed turn the printer off reconnect the wires for the heater cartridge and put the cover back on the heater cartridge is not a polarized device so it doesn't care which wire is connected to the positive terminal and which wire is connected to ground I've used the USB power method to test my Sol vault SP 0 1 which has thermal runaway protection enabled I've also tested my mana price maker select plus printers which I have upgraded with the adv i3 plus plus firmware and they have thermal runaway protection enabled too and I've tested my indoor 3 pro which I've updated to the current reality firmware compiled from source code now the original firmware that it shipped with did not have thermal runaway protection enabled but the current firmware does and so my indoor 3 pro now passes the test if your into 3 or into 3 Pro doesn't pass the test go watch the installing of bootloader updating to the current reality firmware video linked in the description and get your printer updated to get this important safety feature enabled so those are a couple of ways that you can test your printer to see if it has thermal runaway protection enabled test yours and let me know in the comments which printers you tested and which ones do and don't have thermal runaway protection enabled and let me know if you run in the stock firmware or if you've updated it well thanks for making it all the way to the end and things for all of the likes comments and shares now don't forget to subscribe and click the bell so that you don't miss out on any cool 3d printing stuff if you liked this episode give it a thumbs up if not give it a thumbs down but either way please share your thoughts down in the comments and if you like the content that I'm producing and you want to help out check out the description for ways you can do that shopping using the Amazon affiliate link really helps no matter what you're buying and heck even just subscribing is a great way to support the channel and help keep me making these videos for you well now that I'm more confident in my printers thermal safety features I'm gonna go print something cool you do the same and I'll see you next time [Music] you you

Channel: BV3D: Bryan Vines

Views: 42,430

Keywords: 3D Printing, 3D Printing Friends, thermal runaway, 3d printer, thermal runaway 3d printer, how to, thermal runaway protection ender 3, sovol sv01 3d printer, thermal runaway explained, how to test thermal runaway protection, thermal runaway protection

Id: z5s2iXBpnrc

Length: 10min 55sec (655 seconds)

Published: Mon Jan 27 2020