The Desiccant Indicator In Detail - PerkinElmer Spectrum 100 Series User Manual

70 . Spectrum 100 Series User's Guide

The Desiccant Indicator in detail

The optical system of the spectrometer is purged at the factory. This protects the KBr
(Spectrum 100) or CaF
2
windows from being damaged by humidity. Replaceable packs of desiccant maintain the
purge.
The top panel of the instrument includes a Desiccant Indicator, whose sectors change
sequentially from blue to pink as the desiccant becomes exhausted. Change the desiccant
packs in the instrument when the sector marked 10 becomes pink, but while the sectors
marked 15 and 20 are still blue. These numbers correspond to the approximate %
Relative Humidity in the optical compartment.
Pink
Blue
Figure 17 The Desiccant Indicator: When desiccant packs should be changed
If all three sectors of the Desiccant Indicator are pink, then you must
change the desiccant.
CAUTION
The instrument optics may be fogged. Do not switch the instrument
either ON or OFF until all sectors are blue.
Sector Action Required
All sectors blue None. The humidity levels in the instrument are below approximately
10% Relative Humidity.
Sector 10 pink Change the desiccant.
If the instrument has been switched OFF for an extended period, do
not switch ON until you have changed the desiccant and all sectors
are blue.
Sector 10 & 15 You should have changed the desiccant already.
pink
Do not switch the instrument ON or OFF until you have changed the
desiccant and all sectors are blue.
(Spectrum 100N) beamsplitters and the sample compartment
Blue