DETECTORS
Thermal Conductivity Detector - TCD
Overview
TheThermalConductivityDetector(TCD) is themostuniversaldetectoravailable. Dependingon the
compound, theTCD respondswithadetection rangeof0.01% to100% (100-1,000,000ppm). TheSRI
TCDconsistsoffourfilamentshoused inastainlesssteeldetectorblock. TheTCDdetectorblock is installed
in itsown thermostatically-controlledoven forstability. TheTCDoven ismountedon the right rearof the
columnoven. TheTCDfilamentcontrolswitchand thebridge terminalblock towhich thefilament leadsare
connectedare located to the immediate right of thedetectoroven. Since the fourTCD filamentscanbe
damagedordestroyed ifenergized in theabsenceofcarriergas flow, aTCD filamentprotectioncircuit is
provided inallTCD-equippedSRIGCs.
TCDDetectoronanSRIGC
TCDDetectoronanSRIGCwith
detectorcoverand top/front
insulation removed forclarity
Color-coded TCD
filament leads are
connected to the
bridge terminalblock
TCD filamentcurrent
control switch
TCDdetectorovensetpoint (trimpot)
TCDDetector
(pairedwithan
FIDdetector)on
anSRI8610GC
TCDDetectoron
anSRI310GC
Color-coded
filament leads
Insulation
TCDdetector
body
TCDdetector
housing
