Really Fast Heating of the Nozzle...? I have been experimenting with a heater cartridge to heat up my nozzle and I have noticed that it heats up REALLY fast. It will overshoot my target temperature by 30+ degrees and then eventually settle back down and be constant. While it is awesome that the heater cartridge can generate that much heat that quickly, my thermistor doesn't seem to react quickly enough. Is there a setting in the firmware to adjust the amount of times per second that a reading is taken with the thermistor? https://reprap.org/forum/read.php?1,141593,141593#msg-141593 Thu, 12 Mar 2026 18:39:16 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,141593,141822#msg-141822 Re: Really Fast Heating of the Nozzle...? https://reprap.org/forum/read.php?1,141593,141822#msg-141822
In Marlin's configuration.h it has this:
Quote

#define PID_dT ((16.0 * 8.0)/(F_CPU / 64.0 / 256.0)) //sampling period of the

so possibly it can be changed but that will also affect the weight of the Ki and Kd terms.

There is also a PID_MAX setting to limit the current, which would allow it to heat slower.

I would give the Marlin autotune a try before changing anything else.]]> nophead General Mon, 09 Jul 2012 04:45:26 -0400 https://reprap.org/forum/read.php?1,141593,141807#msg-141807 Re: Really Fast Heating of the Nozzle...? https://reprap.org/forum/read.php?1,141593,141807#msg-141807 jbayless General Mon, 09 Jul 2012 01:34:19 -0400 https://reprap.org/forum/read.php?1,141593,141788#msg-141788 Re: Really Fast Heating of the Nozzle...? https://reprap.org/forum/read.php?1,141593,141788#msg-141788 NewPerfection General Sun, 08 Jul 2012 19:25:49 -0400 https://reprap.org/forum/read.php?1,141593,141598#msg-141598 Re: Really Fast Heating of the Nozzle...? https://reprap.org/forum/read.php?1,141593,141598#msg-141598
Need to know which firmware specifically, but yes, there should be adjustments in the firmware/EPROM settings that allow you to tune the PID, assuming you have PID heater control turned on.

Here's how PID controls work.]]> jcabrer General Sat, 07 Jul 2012 02:16:29 -0400 https://reprap.org/forum/read.php?1,141593,141593#msg-141593 Really Fast Heating of the Nozzle...? https://reprap.org/forum/read.php?1,141593,141593#msg-141593 vulcanrd General Sat, 07 Jul 2012 00:30:05 -0400