Marlin sensor_maxtemp is different from the max dialable temp- CR-10S


I’ve recently got CR-10S printer with the latest board and firmware. I installed E3D V6 hotend and made changes to the firmware (temp_sensor 05, heater_0_maxtemp 285).
Arduino IDE compiled the the corrected code and successfully (I assume, no errors encountered) uploaded it to my controller.

However, the control box allows me to increase the nozzle temperature to 270C only.

So my questions are:

  1. Is there a way to re-check if the changes were applied successfully? For example, can I read the maxtemp setting off the board?
  2. If the update was successful, how can you explain the difference, and what should be done to make the control dialing all the way up to the set maxtemp?

P.S. I discussed the issue with another user, and he confirmed that the maxtemps set for the hotend and bed are always about 15 degree higher than the max temperatures allowed to be dialed by the control unit. He had to set maxtemp to 305C to be able to dial up to 290C in the control unit. Any ideas?



Hi Mike,

Here’s a guess: max_temp means just that. Your extruder temp fluctuates as it try’s to maintain a set temp. It needs a little wiggle room to stay on target. If you set your temp to max_temp, it is already at the ceiling and cannot guarantee that it will not exceed that value. So, the system needs a range that the extruder can reach but the user can’t set.



Thank you Stefan. This was my guess too. But I couldn’t find it mentioned anywhere which is really disappointing.

Interestingly enough, e3D suggests 285C in the maxtemp for their V6 all metal hotend. In reality, it’ll produce 270C. The whole purpose of the upgrade is vanished if we follow their directions. :frowning:

It’s tough to be pioneers. :slight_smile:

Thanks again.