Spectrum Two HATR User's Guide . 17
Purging the HATR
With the Spectrum Two spectrometer, you can purge the HATR rather than the sample
compartment. In this way the purge is maintained when you change sample (provided that
you do not remove the top plate) and the purge volume is less.
Use polyethylene tubing with a 6 mm external diameter and a 4 mm internal diameter to
carry the gas to the purge inlet on the HATR.
1.
Loosen the knurled nut on the HATR (Figure 11).
Figure 11 The purge connection on the HATR
2.
Push the tube through the nut until it rests against the interior connector.
3.
Tighten the nut to clamp the tube in place.
4.
Purge the HATR using a flow rate of approximately 1 or 2 l/min.
5.
Monitor the baseline until H
2
O/CO
2
vapor is reduced or negligible.
You should turn off the atmospheric correction in Spectrum software, by deselecting the
CO2/H2O
check box on the Setup Instrument Advanced tab.
Knurled nut
