Getting Started 
20  Agilent Cary 630 FTIR Spectrometer User’s Guide 
Validation 
The MicroLab PC software has three tests appropriate for 
performance validation of the Cary 630 FTIR. Performance validation 
verifies the key aspects of the instrument’s ability to measure good 
data. If the performance validation tests are within specification, the 
spectrometer should provide data that works well with methods 
developed for the Cary 630. As with any instrument, however, results 
can always be verified by running a known sample with the sample-
specific method.  
The validation tests are accessed from the Advanced Features, System 
Check page of the MicroLab PC software. The Cary 630 FTIR system 
should be warmed up for at least 120 minutes before conducting any 
of these tests.  
Performance (signal-to-noise) test 
This test measures the signal-to-noise level at two regions of the 
infrared spectrum: 2,500 cm
-1
 and 1,000 cm
-1
. Both the background 
and sample are measured at 4 cm
-1
 resolution with a one minute 
collection time. This test takes two minutes per test. You can specify a 
number of tests to be conducted. For diffuse reflectance 
measurements, the appropriate sample position must be in place with 
the diffuse gold mirror. No sample is needed when using the Diamond 
ATR sampling accessory. At least 10 tests should be collected in order 
to obtain an accurate picture of the performance. 
Stability test 
This test measures the short-term stability at two regions of the 
spectrum: 3,000 cm
-1
 and 1,000 cm
-1
. Stability is a measurement of the 
baseline differences observed over the selected time period. The test 
measures a background at the beginning, then one sample every 
minute for the duration of the test as specified in the ‘Number of 
minutes’ field in the software. For diffuse reflectance measurements, 
the appropriate sample position must be in place with the diffuse gold 
mirror. No sample is needed when using the Diamond ATR sampling 
accessory. The test results are expressed as %Transmittance 
(difference versus 100%) of maximum deviation during the Stability 
test.