As a leading manufacturer and supplier of Thermal Conductivity
Detectors (TCDs) worldwide, AGC Instruments is able to advise and design
a suitable configuration should it not be standard.
The Thermal Conductivity Detector (TCD) is simple in construction,
inexpensive yet rugged, universal, has excellent sensitivity and is
relatively linear through a wide range. In its use, the sample is not
destructed. It is one of the most widely used detectors in the world
The Thermal Conductivity Detector (TCD) comprises of a metallic block
which contains a cavity through which gas flows. Positioned in this gas
flow are heated elements ( or ).
As each gas has a known thermal conductivity, the method of difference
in these thermal conductivities is the principal upon which it is
based. For this method, two heated elements in two cavities are
required. In Chromatography applications, the carrier gas passes
through one cavity and the sample after being passed through the column
flows through the second cavity. For Process applications a Reference
(or Span) Gas and Sample Gas are used.