A proportional-integral-derivative controller (PID controller) is a control loop feedback mechanism (controller) widely used in industrial control systems. According to Wikipedia, a PID controller calculates an error value as the difference between a measured process variable and a desired setpoint.
Essentially, the controller attempts to minimize the error by adjusting the process through use of a manipulated variable.
Recently, a DangerousPrototypes forum member by the name of carlazar designed a simple soldering iron driver (SSID) with Arduino Uno (Atmel ATmega328 MCU) PID control.
Key features include:
- Minimal number of components.
- Additional control mode – on-off controller (+ PID PWM).
- External power supply.
- Fits into a 90mm x 110mm x 45mm (WxDxH) box.
- Easy assembly.
“The HQ soldering iron HQ20/HQ30 (24V, 48W) was used [for this project],” carlazar wrote in a recent DangerousPrototypes post.
“It has the E-type thermocouple built in (68uV/degC) but you can change that value in software according to the soldering iron that is used (for example K-type is 41uV/degC).”
In terms of actual use, the SSID features:
- UP and DOWN buttons, changes set-point temperature by 5 degC.
- Button SET cycle through set-point temperature presets: 0 – 150 – 280 320 -350 degC.
- Buttons UP and DOWN simultaneously, change the operating controller mode (PID control/on/off control).
Interested in learning more? You can check out carlazar’s original Dangerous Prototype page here.
Atmel | Bits & Pieces 