Datasheet | April 25, 2014

QuadraTherm® 640i/780i Mass Flow Meter Datasheet

Source: Sierra Instruments, Inc.

Traditional thermal sensors have two sensors — one temperature sensor and one velocity sensor, each in a separate probe sheath. QuadraTherm (the term “Quad” meaning “four”) introduces four sensors — three precision platinum temperature sensors and one patented DrySense mass velocity sensor. Sensor performance improvements never thought possible are gained with QuadraTherm as forced convection is completely isolated (the critical variable for measuring gas mass flow rate) by calculating and then eliminating unwanted heat-transfer components, like sensor stem conduction, one of the major causes of false flow readings.