Espresso Machine Control Boards & Brains
What are the espresso machine control board components?
1. The Black box, aka "brain" aka main control unit
2. The keypads, aka "button box"
3. Ribbon cables
What do the components as a whole do?
The control board controls most functions of an espresso machine. For instance, with volumetric espresso machines, control boards allow the shots to be measured accurately by volume with the help of the flowmeters. The shot is started by the barista but the control unit will stop the shot automatically when the pre-defined volume of water has passed through the flowmeter.
Besides controlling the shot volumes, the units also incorporate the water level unit for the steam boilers and the single boiler on an HX machine. So besides controlling the pump and the 3-way solenoid valves attached to each group they also control the pump and the solenoid that fills the steam boiler. The water level unit probe is obviously connected to the control unit.
To recap, the controller has two functions; to control the water level in the steam boiler and to control the volume of water that determines the shot volume.