A simple Raspberry Pi Pico W based espresso machine controller with support for:
- Web interface with no addtional server (runs on mcu) using websockets for real time data
- Shot graph generation in web ui and automatic shot timer
- PID temperature control of boiler with duty cycled SSR
- digital pump control profiles using PSM and robotdyn dimmer
- integrated shot scale with auto tareing and data recording in web app
- OLED display for current temperature, setpoint and SSR duty cycle
- 1kg load cell compatible scale case design and dimmer case
- flow meter measurement, logging and visualization
- pressure transducer for real time pressure data
Can be installed on any espresso machine for temperature control but currently installed on a Calphalon temp iq
USE AT YOUR OWN RISK
BOM ($25 to $100 depending on basic (ssr + pico + max6675) to complete (Add m6 tap, oled, load cell, dimmer, and transducer)
- OLED $7
- SSR $11
- pico w $6
- max6675 $7.69
- m6x1.0 tap and bit for thermocouple mounting on thermoblock using stock M4 hole location $9
- hx711 and 1kg load cell $8
- robodyne zc triac dimmer $15
- 200 psi pressure transducer 1/8 npt $15
- 1/8 npt female tee $6
- 1/8 npt to 4mm ptc connectors $10
- 1k ohm and 2.2k ohm resistors $0.02 ($6 for assorment of 600)
Other parts and tools most people attempting this should already have on hand or have similar:
- jst connectors and crimper
- spade connectors and crimper
- xt connectors (for wiring harness connecting mains to ssr, thermoblock)
- 24 gauge high temp silicone coated wire
- wire stripper
- multimeter (handy for chasing down faulty wires and connections)
- oscilloscope (e.g. to check flowmeter and dimmer function)
- soldering iron
- heat shrink tubing
- electrical tape
- 3d printer (for scale and cases for pico and dimmer)
- thermal paste for thermocouple
- donor usb cables
- 5W usb power supply
- pico w shield/breadboard