A DIY heat plate for soldering / reflow with an ESP32 and SSR
For creating my PCB projects I ordered a heating plate and did the reflow process manually -- switching the plate on and off with a fuse... Then ordered a Solid State Relay (SSR), MAX6675 with thermocouple and a 220V to 5V converter. Together with an ESP32, button, switch and OLED Display I created this minimal example of an reflow oven/plate.
The code is originally generated by ChatGPT - e.g. the PID control section. The plotting of the profile I needed to modify, also added button input functionality. The profile is for Sn63/Pb37 soldering paste but can be changed easily. The OLED display shows the setpoints of the profile as little crosses in a time vs. temperature diagram. The measured temperature is plotted every second.
Inspiration and code snippets I used from Tiny Reflow Controller with OLED display and from uReflowOven (here you also find leadfree reflow profile).
Code is clearly not perfect, but it works quite nicely.
Parts mainly from AliExpress, total costs: ~25$.
| Part | Price [$] |
|---|---|
| ESP32-C3 Board | 6.00 |
| 600W heating plate | 4.10 |
| 220V to 5V converter | 1.80 |
| Solid State Relay 25A | 3.90 |
| MAX6675 | 2.90 |
| Thermocouple K probe | 1.50 |
| OLED Display | 2.50 |
| Buttons / Switch | 0.50 |
| Wood, Screws, Cables | 2.00 |