MK3S+ hotend problem
After changing the nozzle, the hotend heating cartridge systematically burns out during the calibration test (resistance measured at zero). The calibration goes as far as the bed test, then there is a cut-off without an error message and the machine resets. Measuring the resistance of the cartridge shows that it is burnt out. I measured the other voltages, but everything seems normal.
RE: MK3S+ hotend problem
get a new heater cartridge
RE: MK3S+ hotend problem
Thank you for this valuable advice, but after having burned two Hotend cartridges, I think the electrical problem lies elsewhere.
I have measured all the tensions that appear normal, and I have no further avenues of research.
A line of research?
RE: MK3S+ hotend problem
you did not say you had already killed 2 cartridges so the feed to the cartridge is faulty or you fitted 12 volt in stead of 24volt
RE: MK3S+ hotend problem
The cartridges are original PRUSA and the voltages measured are indeed 24v at the power supply and the EINSY box
RE: MK3S+ hotend problem
so either the power supply is faulty or the cartridges or wiring is shorting some where ??
RE: MK3S+ hotend problem
Do you have a volt meter? Can you measure the voltage going to the heater cartridge from the connector on the Einsy?
A quick experiment I just tried with a spare heater, if the Einsy isn't controlling the heater properly, then the heater will overheat and glow red and then burn out. Need the heat sink and thermistor connection to regulate properly. Does the temperature read properly from the hot end thermistor? If you have a cold printer and grab and hold the hot end, does the temperature go up on the display? This is a simple temperature test.
If you have an external thermometer that you can measure with, then slowly manually test the temperature settings and compare the screen to the measured temperature.
After having heating issue, I would be tempted to change the thermistor as it may have gone out of calibration. I had my head melt and the thermistor gave me one temp but the actual temperature was much higher.
RE: MK3S+ hotend problem
Thanks for your advices.
I have already carried out all these checks and changed the thermistor, with no conclusive results yet.
I will disassemble the entire circuit and check the wiring, voltages and temperature step by step.
I will keep you informed of the results.
RE: MK3S+ hotend problem
After total disassembly (including the EINSI) I ended up finding a screw (of unknown origin since I had not opened the EINSI for several months) stuck between two connectors.
I don't understand how the voltages could be correct, but the printer works now.
Thanks for your help.
RE: MK3S+ hotend problem
Glad you got it working.
A piece of metal on a circuit board. You are lucky that it didn't take out the board. It would be interesting to know which connectors it was on. Also would be interesting on how it got there.