Bruker IFS 125M, User Manual, Page: 65 / 228

65 Bruker Optik GmbH IFS 125M User Manual
Operation 5
5.11 Purging the spectrometer
Purging the spectrometer reduces the level of unwanted atmospheric interferents like
water vapor and carbon dioxide inside the spectrometer. Especially water vapor in ambi-
ent air absorbs IR radiation.
Additionally, purging protects humidity-sensitive components (e.g. KBr beamsplitter)
from damage. A KBr beamsplitter must not be exposed to humidity.
NOTE
Spectrometer permanently open:
Water vapor, CO
2
and other atmospheric gases cause unwanted absorptions in the
infrared spectrum range.
➣
Open the spectrometer only if necessary in order to prevent water vapor or other
gases from entering and adhering to the spectrometer inner walls.
When to purge? If the ambient air humidity level inside the spectrome-
ter is too high.
Purge gas: • dry (dew point < -40°C), oil-free and dust-free air
• nitrogen gas
Maximum pressure: 1800 hPa
Sustained gas flow rate: at least 1 l/s
Purging duration: continuously
How to connect purge
gas supply line: see chapter 3.7.3
Table 5.12: Purging features
WARNING
Not using adequate gases for purging:
Some spectrometer components become hot during operation. Risk of fire and/or
explosion.
➣
Never use flammable gases for purging.