Abe wrote in to tell us about his open-source sous-vide kit, called Ember Kit. He writes:
This is a picture of everything you will get with the Ember Kit. The round holes in the face are double-drilled, but both will be completely covered (one by the knob, one by a sticker).
The Ember Kit is a box for controlling a heater (or cooler, or whatever) to maintain the temperature precisely. It uses a chip with the Arduino bootloader to switch the heater on/off according to a dynamic PID control algorithm. It does the switching with a solid state relay (can switch up to 10 A) and reads the temperature with a voltage divider and thermistor.
Some features of the Ember Kit:
Solid state: A solid state relay with integrated heatsink can switch up to 10 A and is built to last. No moving parts, no clicking noises.
Precision Thermistor: For the highest accuracy, we include a submersible thermistor and shielded high-temperature cable.
Arduino-based code: Easily program the controller with an FTDI cable. This means you can have the temperature follow any profile, and it can interface with the computer via USB for data logging and dynamic control.
Custom enclosure face: We’ve already cut holes in the enclosure face to fit the display and knob. You hack it onto your heating device however you want.
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