UNSOLVED heater cartridge degraded and "lost power"

c310

on my duetwifi i have used 24v 60w heater cartridge. it was easily heating up to 310 degrees, but yesterday it was hardly reaching 280.... i checked cables and re-calibrated with M303.
No luck

in my understanding is that heater either works or not. it can not degrade...

am i right?
and where else should i check to fix the issue?

thanks!

Veti

measure the resistance of the heater.
then calculate its power from that.

dc42

Check all connections between the heater and the Duet. Also check the connections between the PSU and the Duet.

If you did any work on the hot end between the heater working and not working fully, check that there is a gap between the bottom of the heatsink and the top of the heater block.

deckingman

,........and check your power supply. M122 will show you the min and max voltage - check that you have 24v when the heater(s) is/are on.

c310

it is 19 Ohms, that gives 30W... that gives half of what it should be

dragonn

This can happen. Actually you are lucky, sometimes can happen that a heater gets a short and just burns out destroying fuses or cables/connectors with it.
Just replace it.

c310

VIN was between 24.5 and 25.0 volts , all cables and connections were in a good shape..

finally, i have replaced it...
and new one works as it should be

thank you all for support!

c310

@dc42 it had happened again are there any parts on the Duet WiFi board that potentially have degraded?

Phaedrux

Would seem strange that any degradation on the duet would get better when replacing the cartridge though, wouldn't it?

60W cartridge would be quite powerful. Perhaps the life expectancy is shorter than a regular 30w.

dc42

@c310 said in heater cartridge degraded and "lost power":

@dc42 it had happened again are there any parts on the Duet WiFi board that potentially have degraded?

The only things I can think of that might have degraded in a way that reduced output power are the soldering of the heater output connector to the PCB, and the soldering of the main VIN fuse holder to the PCB. If those joints are bad, the problem should be easily visible.