Pressure Transducer in (Commercial) Espresso Machines
Water pressure measurement in professional coffee machines is required in the boiler and brewing loops. Pressure instruments must be accurate, able to withstand the temperatures and stresses generated by cleaning processes and have specialized wetted parts, certified for drinking water and food application, as the use of pressure instrumentation is an essential part of safe food production.
To guarantee the constant espresso quality, brew pressure (pump outlet pressure) must be stable. To ensure that, espresso machine manufacturers install an over pressure valve (OPV) at the pump outlet side. An OPV can be adjusted with a screw driver and is not always accessible without dismantling the machine. As manufacturers are constantly improving their technology and considering easy-to-use consumer requirements, modern coffee machines allow regulation of the brew pressure with a single button, which is easily accessible from outside the machine. In this case, an OPV is being substituted by a proportional valve and a pressure transducer, installed behind the valve.
Download this application note to learn more about where exactly pressure sensors are used within espresso machines.