Reflow hot plate update

Arduino projects

Nov 29

In this video, I show my most recent updates for my fully DIY, automated reflow hot plate. I replaced the heater plate with a larger one, I updated the code and implemented a proportional heater instead of an ON-OFF heater, and added a neon glow lamp to the output terminal of the TRIAC to see when the heater is heating.

Additional resources

Useful affiliate links for the parts I used in this project:

Arduino Nano

1.8” TFT LCD

Rotary encoder

MAX6675 thermocouple module

230 V AC to 5 V DC 600 mA PSU

Mica heater

40 mm fan

1.5 mm aluminium plate

Paper clips

Full assembly

I mounted the whole system on an A4 wood sheet. It makes it tidier and easier to handle. I put a PCB on the hot plate to illustrate how large the surface is.

Hot plate

The previous 100 mm x 150 mm plate is replaced with a 150 mm x 150 mm plate. I clamped a 2 mm thick aluminium plate on the mica heater to maintain a flat surface during heating.

New page

The new code contains a second page which allows free heating (maintain a target temperature), and free cooling. The free heating is controlled by a proportional heat control algorithm.

Neon glow indicator lamp

I added this small neon lamp to the output terminal of the TRIAC. It indicates when the hot plate is powered. It is a good feature when we want to see the proportional heater in action.