A hidden/internal PID for Rancilio Silvia based on Arduino.
The original temperature control in the Rancilio Silvia is not the best ever made. It fluctuates from 80s to the 110s C.
As seen in this image, an Arduino with a SSR, and a basic PID, tuned for the Rancilio Silvia does a far better job of holding the temperature at 100 C. This project seeks to optimize this simple setup for stable temperatures and fast recovery after steaming.
Key features of the Arduino PID for Rancilio Silvia:
1 - Completely hidden. My goal is to keep the stock look of the Silvia.
2 - Easy to build
3 - Fast recovery from both cold starts and steaming.
4 - Original buttons work as normal
5 - No limits on how long it can stay powered on.
6 - No additional procedures
7 - Shows how long the pump has been on
Features that I might add:
1 - Boiling point based on actual atmospheric pressure (I don't know yet if this is of any use for making better espresso)
I will upload the schematics and more information as I complete them.
Parts used:
1 - Arduino Mega 2560
2 - MAX31855 Thermocouple
3 - 40A SSR Relay
4 - 230V USB charger (Apple)
5 - A few new wires
6 - Ampmeter for detecting pumping
7 - 4 digit display
Working priciple:
1 - The 100C thermoswitch is replaced with a SSR
2 - The 140C and 165C thermoswitches is still in the loop
3 - The Arduino keeps the temperature at desired setpoint when the Silvia is powered on
4 - The display shows how long the pump has been on, and flashes the total time for some seconds when the pump stops
5 - The steam-button still works as original, and it is ready when the boiler passes 140C