Electric Kiln

ESP32Kiln is an attempt to create versatile and convenient PID temperature controller for the space.

The space had an old kiln left in disrepair by a previous member. Needless to say it required some care to get it back in shape. This documentation is made to keep track of what was made for future members if they need to repair it or understand how it worked. It is based primarily on the work done by Saur0o0n and modified by me amd989 to have some quality of life enhancements.

So the electric kiln is a PID temperature controlled kiln, for any task involving high temperatures - like burning ceramic, glass fusing, soft metal melting, burning lost wax casting forms - and probably much more.

It has many neat features!

Main ESP32Kiln features

• Interface accessible both from LCD screen and WWW Webpage
• Unlimited (limited only by storage) temperature programs number, program file size limited to 10KiB (but this is artificial limit - can be extended)
• Internal ESP SPIFFS storage for programs, data, logs, configuration (perhaps later SD - but I'm not sure yet)
• Local preferences on disk, editable with Web interface
• Online monitoring, program management, editing, graphs and kiln control
• Build in clock synchronised with NTP servers (if Internet connected)
• Safety features build in (temperature run out protection, probe failure, SSR failure, kiln insulation failure)
• Online ESP32Kiln firmware upgrade with web interface
• Auto PID Calibration (WIP)

Navigation (WIP)

• Components
  • Hardware Components
  • Software
• Installation
  • Hardware Assembly
  • Software Installation
• Usage

• • LCD Interface
  • Web Interface
  • Preferences
  • Program Structure

Known Bugs

• When there is file upload error (file name too long, file too long etc.) - next upload (in the same session) will not start. Another one will be ok. This is something in webserver, when you brake client connection in not too clean way.
• ESP (at least mine) has a bad habit of hanging network connection. This you will experience as being unable to load page (it hangs on loading). In this scenario ESP usually did a kill/reboot of itself with Watchdog. But since this could be dangerous to our running program I've disabled this feature, so now WWW will hang indefinitely. But program will run (with all the features) and LCD will work. Perhaps later, Espressif will fix this issue.
• Directly connected to above problem, usually ESP hangs when transmitting/reading large portion of data (that's kind of obvious). Initially I've stored all JavaScript files locally, in case if PIDKiln will be used without Internet connection. But all Charts.js and JQuery weight around 500KiB - that's a lot. So now this files are loaded from external network. If your installation doesn't have it - there is an option in Preferences to set, if those files should be fetch from Internet or not. Also in PIDKiln 1.1+ JS files are compressed (so the risk is smaller).
• When ESP32 creates AP, from time to time there is a DHCP problem (it will reboot device) - if this is your case. Disable DHCP on your smartphone/laptop and use static IP 192.168.10.2/24.