Reflow Oven Controller
Arduino-based reflow oven controller with:
- PID loop control
- Wave Packet and Phase Fired control for AC outputs
- graphic TFT LC-Display, drawing the temperature curves
- using an Adafruit 1.8″ TFT or derivate display
- solely controlled using a cheap rotary encoder and it’s single button
- stores up to 30 temperature profiles in EEPROM
- configurable PID-parameters
- simple, small hardware to drive loads up to 600V and up to 8A
- hardware can
- measure two temperatures independently
- drive two AC loads, such as heater and fan
- could also be used for slow coockers
(c) 2014 Karl Pitrich karl@pitrich.com in part based on a project (c) 2013 Ed Simmons ed@estechnical.co.uk
Warning: This project operates with possibly lethal mains voltage. If you are unsure what to do, don’t do it and get help from an experienced tinkerer with professional training.
Post action shot:
Introduction
This Reflow Oven Controller relies on an Arduino Pro Micro, which is similar to the Leonardo and easily obtainable on eb*y for less than $10, plus my custom shield, which is actually more like a motherboard.
As I believe it is not wise to have a mess of wiring and tiny breakout-boards for operating mains powered equipment, I’ve decided to design custom board with easily obtainable components.
The hardware can be found in the folder hardware, including the Eagle schematics and PCB layout files. It should fit the freemium version of Eagle. Here are preview images:
From my manufacturing run, I have some spare PCBs. You can contact me to get some (€15,- + p&p each).
The board contains the Arduino Pro Micro, very simple Zero crossing detection circuit, used to align control logic to mains frequency, two MAX31855 thermocouple-to-digital converters and two Sharp S202S01 PCB-mount solid state relays, mounted on cheap Fischer SK409 50,8 heat sinks. The current software uses only one of the thermocouples, so you need to populate one IC only. If you’re lucky, you can get free samples of the MAX31855 from Maxim.
For more detail: Reflow Oven Controller with graphics TFT