Thermo Scientific Nicolet iS50 GC-IR User manual

Nicolet iS50 FT-IR Spectrometers
iS50 GC-IR Module
User Guide
269-278100 Revision A July 2012

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Thermo Scientific iS50 GC-IR Module User Guide 1
iS50 GC-IR Module
This section describes the Thermo Scientific iS50 GC-IR module which is an optional
sampling module for your Nicolet™ iS™50 spectrometer.
Conventions Used in This Document or Help System
This manual uses these conventions for providing safety and other special information:
Contents
•About the GC-IR Module
•Important Features
•Specifications
•Operating Precautions
•Compatible Software
•GC-IR Sampling
•Setting Up the GC-IR System
•Checking Performance
•Samples Compatible with GC-IR
•Your First Experiment
•Maintenance
•Troubleshooting
NOTICE Be sure that all persons operating this system read the site and safety manual
first.
WARNING Indicates a hazardous situation which, if not avoided, could result in death or
serious injury.

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2iS50 GC-IR Module User Guide Thermo Scientific
About the GC-IR Module
The iS50 GC-IR module allows you to combine the separating power of a gas chromatograph
(GC) with the selectivity of an infrared spectrometer. The GC-IR module is compatible with
the Nicolet™ iS™50 FT-IR spectrometer and the following gas chromatographs and
autosamplers:
• Thermo Scientific TRACE™ 1300 series gas chromatographs with autosamplers
• Agilent™ 7890 gas chromatograph
Figure 1. iS50 GC-IR system
Before operating the GC-IR module, you should be familiar with the fundamentals of
capillary gas chromatography and the operating characteristics of your FT-IR spectrometer
and GC.
CAUTION Indicates a hazardous situation which, if not avoided, could result in minor or
moderate injury.
NOTICE Follow instructions with this label to avoid damaging the system hardware or
losing data.
Note Contains helpful supplementary information.
Tip Provides helpful information that can make a task easier.
The GC-IR module mounts on the right
side of the Nicolet iS50 spectrometer
Nicolet iS50
FT-IR spectrometer iS50 GC-IR module
Thermo Scientific
TRACE 1310 GC

iS50 GC-IR Module
Thermo Scientific iS50 GC-IR Module User Guide 3
A Thermo Scientific TRACE 1310 GC is shown in the illustrations in this document.
Installation procedures for injectors, detectors and columns are explained in the operating
guides provided with the GC and will not be reproduced here. For instructions to connect
your column to the GC-IR module transfer line, see “Setting Up the GC-IR System.”
The iS50 GC-IR module provides these enhanced features:
• Integrated design
• Push button configuration
• High efficiency optics
• Dedicated, highly sensitive detector
• Software-controlled transfer line and flow cell temperature
• Support for GC autosamplers
For information about additional sampling modules and accessories for your Nicolet iS50
spectrometer, contact our sales representative in your area.
Important Features
This section describes the major features of the iS50 GC-IR module.
From the Front
Figure 2. iS50 GC-IR module front view
These features are visible from the front and sides of the GC-IR module:
•External beam port. Light from the spectrometer passes through this port to the flow cell
in the GC-IR module. Your iS50 GC-IR module may have an optional KBr window
installed in the external beam port.
GC-IR Touch Point
External
beam port
Transfer lineDetector fill port

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4iS50 GC-IR Module User Guide Thermo Scientific
•Transfer line. Vaporized sample from the GC passes through this precisely heated line to
the heated flow cell inside the GC-IR module. The flow cell is where the sample interacts
with the infrared beam to produce the signal for the GC-IR detector.
•Detector fill port. Used to add liquid nitrogen to the dewar to cool the GC-IR detector
before each use. For more information, see “Cooling the GC-IR Module Detector.”
•Touch Point. Automatically configures the spectrometer for GC-IR sampling. The Touch
Point LED shows the status of the GC-IR module. The LED has three states described
below.
Table 1. GC-IR status indicator states
Back Panel Features
Figure 3. iS50 GC-IR module back panel
LED status Meaning
On Ready for use
Off System is not configured for GC-IR sampling
Blinking Optics are reconfiguring
Purge
Accessory (Detector)
AC power
Power switch
Exhaust vent Computer

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Thermo Scientific iS50 GC-IR Module User Guide 5
Related Topics
•Connecting a Purge Source
•Cabling the GC-IR Module
•Resetting the Circuit Breaker
•Venting the GC-IR Module Exhaust
•Maintaining the Carbon Filter
Specifications
Table 2. Specifications for the iS50 GC-IR module
Feature Description
Purge Connects to the purge gas supply. For more information, see
“Connecting a Purge Source.”
Accessory Connector for the detector cable. See “Cabling the GC-IR Module”
for details.
Computer Connector for the USB communications cable
AC power Connector for the power cord.
Power switch Powers the GC-IR module on and off. A built-in circuit breaker
automatically shuts off power to the instrument if an over-current
condition occurs. For information on recovering from an over current
condition, see “Resetting the Circuit Breaker.”
Exhaust vent Effluent leaving the flow cell travels to a room temperature carbon
filter and then out this vent. The vent can be routed to a fume hood if
needed; see “Venting the GC-IR Module Exhaust” for details.
WARNING Your GC accessory is preset to work with the correct AC line voltage in your
country. To avoid shock and fire hazard, do not attempt to change the setting. Contact
our customer support if your system does not meet your local power standards.
Feature Specification
Compatible gas chromatographs • Thermo Scientific TRACE 1300 series
• Agilent 7890
Maximum temperature of
transfer/exhaust lines and flow cell
300 °C
Temperature status output Continuous
Detector Dedicated nitrogen-cooled MCT-A

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6iS50 GC-IR Module User Guide Thermo Scientific
Operating Precautions
• Make sure the spectrometer is fully purged before you turn on the GC-IR transfer line
and flow cell heaters to prevent damage to the KBr windows in the flow cell. For more
information, choose Help > Spectrometer Help Topics and search for the “Checking the
Purge” topic.
• To prevent the flow cell windows from becoming contaminated, do not turn on the flow
cell or transfer line heaters unless a GC column is installed and the helium make-up gas is
flowing through the flow cell.
• Pieces of graphite, column or dirt in the transfer line or connecting Tee union may enter
the flow cell and block the infrared beam. Keep the Tee union and transfer line clean and
free of debris.
• Do not attempt to slide a wide-bore (0.53 mm I.D.) column through the transfer line.
These columns may become lodged in the Tee union and block the transfer line.
• Avoid spilling excessive amounts of liquid nitrogen on the outer housing of the GC-IR
detector dewar. Repeatedly cooling the MCT detector window and the seals in the
vacuum valve can cause the dewar to lose its vacuum.
Compatible Software
Table 3. Software compatible with the GC-IR module
Software Use for...
OMNIC Series Collecting, processing and searching time series data including
GC-IR, TGA-IR, rapid scan and kinetics data. Includes Mercury GC,
a dedicated tool for GC-IR analysis (automated profile peak finder
and multi-component search). For more information, find
Mercury GC in the Series Help Topics.
OMNIC™ Configuring your GC-IR workflow, including quantitative analysis
and spectral search, and collecting and analyzing GC-IR spectra. For
more information, see the “Your First Experiment” section.
OMNIC Specta™ Analyzing unknowns. This software includes our unique
multi-component search feature for identifying the spectra of
mixtures, a 9,000 compound spectral database, and features for using
your computer’s hard drive as a library. For more information, refer to
the Help system in OMNIC Specta software.
TQ Analyst Creating quantitative and classification methods that can be used with
OMNIC. This software provides an extensive suite of chemometrics
features you can use to identify raw materials, perform quantitative
analysis, and take spectral measurements. For more information, refer
to the help system in your TQ Analyst software.

iS50 GC-IR Module
Thermo Scientific iS50 GC-IR Module User Guide 7
GC-IR Sampling
In a GC-IR experiment the sample is injected into the column of a gas chromatograph which
separates the sample components. The GC column is routed through a heated glass-lined,
stainless-steel transfer line to the GC-IR module. Effluent leaving the GC column
immediately enters the flow cell, where it is scanned by the infrared beam. In effect, the
infrared spectrometer is a chemically specific detector for the gas chromatograph, sensitive
only to compounds that absorb infrared radiation.
The flow cell and its fittings are coated with gold, making them inert to materials entering
from the GC column. Dedicated controllers maintain the temperature of the flow cell and
transfer line.
When a standard capillary column is used, a make-up gas is added to the transfer line. This
gas flows around the GC column in the transfer line to prevent backflow. The make-up gas
also carries the effluent through the larger diameter flow cell with minimal loss of
chromatographic resolution. The stream exits the flow cell and travels through an exhaust line
to an unheated carbon filter, which vents out the back of the GC-IR module.
The GC-IR module performs best with standard capillary chromatography columns.
However, you can also use it with wide-bore capillary columns. In this case, the column is
connected directly to the transfer line. No make-up gas is required because of the higher flow
rates used in wide-bore column gas chromatography. For instructions on connecting columns
to the GC-IR module, see “Setting Up the GC-IR System.”
Related Topics
•Setting Up the GC-IR System
•Setting Flow Cell and Transfer Line Temperature
•Maintaining the Carbon Filter
Setting Up the GC-IR System
After the GC-IR module has been installed by our representative, you are ready to connect a
purge source and the transfer line, make-up gas line, column and GC detector, if desired. This
section explains how to connect these items and also describes how to prepare the system for
running GC-IR experiments.
•Cabling the GC-IR Module
•Connecting a Purge Source
•Connecting the Transfer and Make-up Gas Lines
•Installing a Standard Capillary GC Column
•Installing a Wide-Bore Capillary GC Column

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8iS50 GC-IR Module User Guide Thermo Scientific
•Connecting the GC Detector
•Venting the GC-IR Module Exhaust
•Measuring and Adjusting the Make-up Gas Flow Rate
•Cooling the GC-IR Module Detector
•Setting Flow Cell and Transfer Line Temperature
•Recommended Column Flow Rates
Cabling the GC-IR Module
This section describes the electrical, purge and exhaust connections for the iS50 GC-IR
module.
Table 4. iS50 GC-IR module electrical, purge and exhaust connections
CAUTION Avoid burn hazard. Do not touch the bare transfer line, flow cell or vent line
when the insulation has been removed and the heaters are on. Temperatures can exceed
300 °C (572 °F).
WARNING Avoid inhaling GC-IR module exhaust. Keep the work area properly
ventilated or connect the exhaust vent to a fume hood.
WARNING Avoid explosion hazard. Never use a flammable, combustible, or toxic gas to
purge this instrument. The purge gas must be free of oil and other reactive materials. Heat
from the source or from laser absorption may ignite flammable gases or reactive materials
in purge gas. Use only dried air or nitrogen to purge your instrument.
Connection Description
Purge Connects to the purge gas supply. For more information, see
“Connecting a Purge Source.”
AC power Plug the AC power cord into this receptacle and then into an AC wall
outlet.
Detector Plug one end of the detector cable into the Accessory port on the back
of the GC-IR module. The other end goes to the Accessory port on
the back of the spectrometer. (The spectrometer has a right and left
Accessory port. Use the one that is closest to the GC-IR module.)

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Thermo Scientific iS50 GC-IR Module User Guide 9
Related Topics
•Back Panel Features
•Venting the GC-IR Module Exhaust
•Connecting a Purge Source
Connecting a Purge Source
The GC-IR module must be purged with dry air or nitrogen. The spectrometer window and
beamsplitter configuration needed for the GC-IR module also require that the spectrometer is
purged (using only desiccant is insufficient). The purge gas requirements for the GC-IR
module are the same as for the spectrometer.
We recommend using dry air supplied by a purge gas generator or pure air generator (available
from us), or nitrogen. Please refer to your Site and Safety Information guide for specific purge
gas requirements.
Exhaust Connect a length of 1/8 in diameter plastic tubing to the Exhaust port
on the back of the GC-IR module. Route the other end to a fume
hood if necessary. For more information, see “Venting the GC-IR
Module Exhaust.”
Note: You can connect a flow meter to the exhaust vent to measure the
carrier gas flow rate through the flow cell.
Remote trigger
(optional)
Connect the 37-pin D-type connector of the remote start cable to the
Auxiliary Signals port on the back of the spectrometer. Connect the
BNC connector of the cable to the data collection trigger signal for
your GC. For more information, see the documentation that came
with your GC.
To set up the remote start cable in OMNIC software:
1. Start OMNIC software.
2. Choose Collect > Experiment Setup, select the Series tab and
select External Trigger.
CommunicationsaThis USB cable runs the temperature controllers in the GC-IR
module. Plug one end of the cable into a USB connector on the
computer. Connect the other end to the Computer USB port on the
back of the GC-IR module.
aThe Agilent 7890 GC requires an Ethernet cable instead of a USB cable.
Connection Description

iS50 GC-IR Module
10 iS50 GC-IR Module User Guide Thermo Scientific
The purge input connector is on the back of the GC-IR module (see the illustration in “Back
Panel Features”). For information on how to install the purge equipment, set the controls, and
inspect and clean the filter, find “Installing a Purge Kit” in Spectrometer Help Topics.
Adjust the GC-IR module purge gas supply pressure and flow rate as described in the table
below.
We recommend that you leave the purge on at all times. This keeps the GC-IR module free of
undesirable gases, protects the optics and improves the system’s thermal stability.
Related Topics
•Back Panel Features
Connecting the Transfer and Make-up Gas Lines
The transfer line and the make-up gas line are connected by a stainless-steel Tee union. The
third opening on the Tee union connects to either the GC column or a splitter if the GC
column is routed to both the IR detector and the GC detector.
WARNING Avoid explosion hazard. Never use a flammable, combustible, or toxic gas to
purge this instrument. The purge gas must be free of oil and other reactive materials. Heat
from the source or from laser absorption may ignite flammable gases or reactive materials
in purge gas. Use only dried air or nitrogen to purge your instrument.
NOTICE Do not use argon as a purge gas. Argon is an insulator and prevents the system
from cooling properly.
Table 5. Recommended purge pressure and flow rate for the iS50 GC-IR module
Purge Pressure Purge Flow
20 psig 10 SCFH
NOTICE To protect flow cell windows from contamination, make sure a GC column is
installed and helium make-up gas is flowing through the flow cell before you turn on the
flow cell or transfer line heaters.

iS50 GC-IR Module
Thermo Scientific iS50 GC-IR Module User Guide 11
Figure 4. iS50 GC-IR module column connections (without the splitter)
This union is used for all capillary GC applications. We connect the Tee union during
installation. You will need these instructions only if you are converting from wide-bore
capillary columns to standard capillary columns.
Figure 5. Transfer line and make-up gas line connections
GC injector
Make-up gas
line
GC Column
Tee union
Transfer line (to GC-IR module)
Larger I.D. cap nut
1/16 in (0.2 cm) O.D. stainless-steel,
glass-lined transfer line
Graphite ferrule
(size GFF/16)
Make-up gas
line
Smaller I.D. cap nut
Graphite ferrule
(size GFF/16)
Tee union

iS50 GC-IR Module
12 iS50 GC-IR Module User Guide Thermo Scientific
To connect the transfer line and the make-up gas line
1. Locate a Tee union in your GC-IR accessory kit.
You should also find some graphite ferrules. Look at the cap nut on each end of the
straight-through portion of the Tee union. The nut with the larger internal diameter
(I.D.) secures the transfer line. The smaller I.D. nut attaches the column (or a splitter if
one is used). The make-up gas line attaches to the perpendicular stem of the Tee union.
2. Connect the transfer line to the Tee union.
a. Remove the larger I.D. cap nut from the straight-through portion of the Tee union.
b. Slide the cap nut over the transfer line.
c. Carefully slide a size GFF/16 graphite ferrule onto the transfer line, taking care not to
plug the transfer line with graphite from the ferrule after you slide it over the end.
d. Feed the transfer line through the Tee union until the line stops, and then back out
the line about 1 mm.
The transfer line should go almost all the way through the union before it stops.
e. Tighten the cap nut finger-tight.
3. Connect the make-up gas line to the Tee union.
a. Remove the cap nut from the perpendicular arm of the Tee union.
b. Slide the cap nut over the make-up gas line.
c. Carefully slide a size GFF/16 graphite ferrule onto the make-up gas line, taking care
not to plug the line with graphite after you slide the ferrule over the end (use the same
technique as in step 2 above).
d. Feed the make-up gas line into the Tee union until the line stops and then tighten the
nut finger-tight.
4. Use a 5/16-in and 1/4-in wrench to tighten the cap nuts for the transfer and make-up gas
lines.
Turn the nuts about one full turn past finger-tight.
Related Topics
•Installing a Standard Capillary GC Column
•Installing a Wide-Bore Capillary GC Column
•Measuring and Adjusting the Make-up Gas Flow Rate
Tip If you have a scribe tool with a narrow tapered end, you can slide the ferrule onto
the scribe and then insert the point of the scribe into the transfer line and slide the
ferrule off the scribe and onto the transfer line. This technique prevents graphite from
the ferrule from getting inside the transfer line.

iS50 GC-IR Module
Thermo Scientific iS50 GC-IR Module User Guide 13
Installing a Standard Capillary GC Column
This section explains how to install a standard 0.25 mm or 0.32 mm I.D. fused silica capillary
column into your iS50 GC-IR system. These types of columns connect to the GC injection
port at one end. The other end must be fed through the Tee union and transfer line and into
the flow cell of the GC-IR module.
Figure 6. Connections for a standard capillary GC column
To install a standard (0.25 mm or 0.32 mm I.D.) capillary GC column
1. Attach the column inlet to the injection port on the GC.
Refer to the operating guide that came with your GC for specific instructions.
2. Start the OMNIC software.
You will watch a live interferogram while attaching the other end of the column. This will
help you determine how far to insert the column into the flow cell.
3. Choose Collect > Experiment Setup and select the Bench tab.
4. On the Bench tab, set Sample Compartment to GC-IR.
Note If a splitter is used to connect the GC detector, the GC column attaches to the
GC injection port as described above. The other end of the column attaches to the open
end of the splitter instead of the Tee union. For details, see “Connecting the GC
Detector.”
Note If a splitter is used to connect the GC detector, stop here and follow the
instructions in “Connecting the GC Detector” to connect the other end of the
GC column to the splitter.
Transfer line
Tee union
Larger I.D. cap nut
Smaller I.D. cap nut
Standard
capillary
GC column
Graphite ferrule (size GFF/005 for
0.25 mm and 0.32 mm I.D. columns)

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14 iS50 GC-IR Module User Guide Thermo Scientific
5. Locate the Tee union that joins the transfer and make-up gas lines. Remove the cap nut
and ferrule from the free arm of the straight through portion of the Tee union.
6. Thread the free end of your GC column through the cap nut and a ferrule that fits onto
the column.
7. After you have fed the column through the graphite ferrule, remove 2 to 3 mm from the
end of the column to create a clean end with no burrs or jagged edges.
To do this, score the column with a tool or scribe intended for this purpose and snap off
the end piece.
8. While watching the live display at the left side of the Bench tab, carefully feed the column
through the Tee union and transfer line and into the flow cell.
The live display shows the detector signal. The signal is represented both as an
interferogram (if the Single Beam check box is cleared) and numerically as minimum and
maximum voltage values (if the Min/Max check box is selected). Refer to the OMNIC
Help system if you need more information on Experiment Setup and the live display.
9. When the column enters the flow cell, it will block the infrared beam, causing the height
of the interferogram in the live display to decrease markedly.
You may have trouble guiding the column through the opening in the end cap of the flow
cell. Do not force it, as this may damage or break the end of the column. Instead, rotate
the column gently between your fingers while slowly pushing it further into the transfer
line.
10. Slowly withdraw just enough column so that the interferogram regains its original height.
11. Use a 5/16-in wrench and a 1/4-in wrench to tighten the column nut on the Tee union
until you feel the nut start to offer resistance. Then tighten the nut another one-quarter
turn.
12. Choose OK to close Experiment Setup.
Related Topics
•Installing a Wide-Bore Capillary GC Column
•Connecting the Transfer and Make-up Gas Lines
•Connecting the GC Detector
NOTICE Pieces of graphite, column or dirt in the transfer line or Tee union may
enter the flow cell and block the infrared beam. Keep the Tee union and transfer lines
clean and free of debris.
Note If you still cannot get the column to block the beam, just feed in the column as
far as it will go. Some capillary columns are too large to fit through the end cap.

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Thermo Scientific iS50 GC-IR Module User Guide 15
Installing a Wide-Bore Capillary GC Column
These columns have an outside diameter that is nearly the same size as the inside diameter of
the transfer line. To prevent scratching or breakage inside the transfer line, do not try to feed
these columns into the flow cell as described in the previous section. Instead, thread the end of
the column through the Tee union and a few millimeters into the transfer line as described
below. Since the transfer lines are lined with glass, connecting the column this way does not
adversely affect GC-IR performance.
Figure 7. Connections for a wide-bore capillary GC column
To install a wide-bore (0.53 mm I.D.) capillary GC column
1. Attach the column inlet to the injection port of the GC.
Refer to the operating guide that came with your GC for specific instructions.
2. Locate the Tee union that joins the transfer and make-up gas lines. Remove the cap nut
and ferrule from the free arm of the straight-through portion of the Tee union.
3. Thread the free end of your GC column through the cap nut and a ferrule that fits onto
the column.
4. Remove 2 to 3 mm from the end of the column to create a clean end with no burrs or
jagged edges.
To do this, score the column with a tool or scribe intended for this purpose and snap off
the end piece.
Note If a splitter is used to connect the GC detector, stop here and follow the
instructions in “Connecting the GC Detector” to connect the other end of the
GC column to the splitter.
Transfer line
Tee union
Larger I.D. cap nut
Smaller I.D. cap nut
Wide-bore
capillary
GC column
Graphite ferrule (size GFF/10
for 0.53 mm I.D. column

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16 iS50 GC-IR Module User Guide Thermo Scientific
5. Feed the column through the Tee union and a few millimeters into the transfer line.
6. Use a 5/16-in and a 1/4-in wrench to tighten the column nut on the Tee union one-half
turn past finger-tight.
Related Topics
•Installing a Standard Capillary GC Column
•Connecting the Transfer and Make-up Gas Lines
•Connecting the GC Detector
Connecting the GC Detector
You can connect the GC column to any detector installed on the GC by redirecting a portion
of the column effluent through a splitter. Although this is not required for GC-IR operation,
it allows you to monitor the GC chromatography during GC-IR experiments to make sure
you are getting the expected separation. You may omit this step if desired and connect the
GC column directly to the Tee union as described in the previous sections.
To connect the column to the GC detector, you will need a 10:1 splitter kit (see our local sales
or service representative to order the correct splitter). The kit includes a splitter body, extra
ferrules and two lengths of capillary tubing that are joined at one end by a special ferrule. The
internal diameter of the slightly darker tubing is 10 times larger than that of the lighter one,
which produces the 10:1 split ratio. In the package, the smaller diameter tubing is coiled more
tightly than the larger diameter tubing. Before you remove the coils from the package, make
sure you mark one of the coils so you can tell them apart during assembly.
The GC column attaches to the short end of the splitter (see the diagram below). The joined
end of the two lengths of capillary tubing connects to the long end of the splitter. The larger
diameter tubing from the splitter connects through the Tee union and transfer line to the flow
cell. The smaller diameter tubing connects to the GC detector.
NOTICE Pieces of graphite, column or dirt in the transfer line or Tee union may
enter the flow cell and block the infrared beam. Keep the Tee union and transfer lines
clean and free of debris.
NOTICE Do not attempt to feed the wide-bore column through to the flow cell. The
column may become lodged in the Tee and cause blockage of the transfer line.

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Thermo Scientific iS50 GC-IR Module User Guide 17
Figure 8. GC detector connection using a 10:1 splitter
To connect the GC detector
1. Connect the joined end of the splitter tubing to the splitter body.
a. Remove the cap nut from the long end of the splitter body.
b. Thread the free ends of the two lengths of capillary tubing from the splitter through
the cap nut (the lines are joined by a ferrule so no additional ferrule is needed).
c. Screw the cap nut back onto the splitter body and tighten it with two 1/4-in
wrenches.
2. Connect the GC column to the splitter.
a. Remove the cap nut from the short end of the splitter body.
b. Thread the free end of your GC column through the cap nut and a ferrule that fits
onto the column.
c. Remove 2 to 3 mm from the end of the column by scoring it with a column cutter
and snapping off the end piece. This creates a clean end with no burrs or jagged
edges.
3. Connect the larger diameter (darker) capillary tubing from the splitter body to the Tee
union that joins the transfer line and make-up gas line.
a. Remove the cap nut from the free arm of the Tee union.
NOTICE Pieces of graphite, column or dirt in the splitter, transfer line or Tee
union may enter the flow cell and block the infrared beam. Keep these connectors
and lines clean and free of debris.
Graphite ferrule (use appropriate
size for your column)
GC columnCap nut
Smaller diameter (lighter) capillary tubing
connects to GC detector using new GFF/005 ferrule
Larger diameter (darker) capillary tubing
connects to Tee union using new GFF/005 ferrule
Cap nut

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18 iS50 GC-IR Module User Guide Thermo Scientific
b. If there is a ferrule inside the cap nut (from a previous connection), make sure you
remove the ferrule.
c. Thread the darker capillary tubing from the splitter through the cap nut and then
add a new graphite ferrule that fits onto the tubing (several GFF/005 ferrules are
provided in the splitter kit).
d. Remove 2 to 3 mm from the end of the tubing as described above to create a clean
edge.
e. Follow steps 2 through 12 in the “Installing a Standard Capillary GC Column”
section to feed the tubing through the transfer line and into the flow cell.
4. Connect the smaller diameter (lighter) capillary tubing from the splitter body to the GC
detector using a new graphite ferrule from your splitter kit and removing 2 to 3 mm from
the end of the tubing to create a clean edge.
Follow the instructions in the operation manual for your gas chromatograph.
Related Topics
•Connecting the Transfer and Make-up Gas Lines
•Installing a Standard Capillary GC Column
•Installing a Wide-Bore Capillary GC Column
Venting the GC-IR Module Exhaust
Effluent leaving the flow cell travels through a heated transfer line to a room temperature
carbon filter and then to the exhaust vent. The carbon filter absorbs the GC components in
the effluent before they reach the vent.
To connect an exhaust line to the GC-IR module
1. Connect a length of 1/8-in diameter plastic tubing to the exhaust vent on the back of the
GC-IR module.
The other end can be routed to a room vent or fume hood if necessary.
Related Topics
•Back Panel Features
•Maintaining the Carbon Filter
WARNING Avoid inhaling GC-IR module exhaust. Keep the work area properly
ventilated or connect the exhaust vent to a fume hood.