Device and method for calibration of sensors

摘要

A device for calibrating a gas sensor comprises a block (7) of material having at least one channel or passage (8) to increase the surface area thereof, the material of the block having a thermal conductivity greater than 10Wm<-1>K<-1>, a circuit (1, 8, 3) for passing a gas over the surface of said block and temperature sensing means (3) which are disposed in the block in thermal contact with the point in the circuit where the gas leaves the block. The device can be used in a method of calibrating humidity sensors which involves saturating the surface of the block with water and then passing the gas over the saturated surface to establish thermal equilibrium at the temperature of the block and so produce a gas of defined dewpoint. A heater (9) and cooling coil (12) allow the temperature of the block (7) to be controlled.