Thermo Scientific FOCUS GC, Instruction Manual

Page: 182 / 356

Chapter 9
Thermal Conductivity Detector (TCD)
Detector Signal Parameters
182 Instruction Manual
OPERATING SEQUENCE
Programming a TCD
When a wide-bore or capillary column is used, the make-up gas line is required.
Materials required:
• bubble flow or electronic flow meter
Before you begin, do the following:
• Verify that all detector gases are connected, a column is correctly installed,
and the system is leak free.
• Check the oven temperature and injector temperature.
• Check the carrier gas flow depending on the packed or capillary column in
use.
• When a wide-bore or capillary column is used, make sure the make-up gas
line is turned
ON
.
WARNING! Hydrogen is a potentially dangerous gas. Refer to Using Hydrogen for safety
information.
1. In Main Menu move the cursor until
Detector
is selected. Press ENTER to
display the
DETECTOR
menu.
2. Adjust and measure the reference gas flow as follows:
a. Scroll to
Ref flow
and set
ON
, then adjust the flow rate.
b. Adjust the reference flow by operating on the relevant flow regulator
c. Measure the flow after stabilization. Repeat this step until the reference
gas flow rate is correct.
3. Adjust and measure the make-up gas flow, when required, as follows:
a. Scroll to
Mkup flow
and set
ON
, then adjust the flow rate.