In recent years, gas sensors are increasingly used in the growing markets
of systems for gas analysis in the automotive industry and for medical and
environmental monitoring. Gas detection based on thermal conductivity is
widely used in process control and in gas chromatography.
Thermal conductivity detectors (TCD’s) are particularly suitable for detecting
hydrogen, since the thermal conductivity of hydrogen is about 7 times higher
than air. Thermal conductivity gas sensors are especially suitable in safety
applications for fuel cells. In such systems, leakage of hydrogen needs to be
detected before hydrogen concentrations reach the lower explosive limit
(LEL) of 4% in air. The most common TCD technique is made using silicon
technology, which is based on a thin metal wire, usually made of platinum.
The wire simultaneously operates as both the heater and sensing element.
The wire and the surrounding medium under investigation are heated by
applying a constant electrical current.

Application

• Replace traditional TCD in gas chromatography (GC)
• Leak detection for Natural Gas (CH4), Hydrogen (H2), and refrigerant gases
• Natural gas quality control
• Natural gas engine combustion control
• Fuel cell applications
• Carbon Dioxide (CO2) monitoring for Indoor Air Quality (IAQ)
• Methane (CH4) detection for mining safety
• Pirani vacuum gauge
• Measurement of concentration of Helium, Hydrogen, etc. in air and other gases
• Measurement of thermal conductivity and gas type
• Measurement of binary gas-mixture composition

Features

• Extremely low power consumption
• Operate in high temperature environment
• Very stable long-term operation
• Minimal field maintenance required