Bruker HYPERION, User Manual

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61 Bruker Optik GmbH HYPERION User Manual
Operation 4
Special notes regarding the FPA detector
• Always cool down the FPA detector with liquid nitrogen first. Then switch on the
detector. This sequence of actions is necessary to ensure a trouble-free opera-
tion of he FPA detector.
• When the FPA detector is switched on, the nominal hold time is 8 hours. When it
is switched off the nominal hold time is 12 hours. For this reason it is advisable to
switch off the FPA detector if it is not in use.
➣ Note: The ON/POFF switch of the FPA detector is at the bottom side of the right
detector comportment.
2
Liquid nitrogen boils and splashes at first when it is poured in a warm container. Especially
at the beginning when die temperature difference between detector dewar and liquid nitro-
gen is still very large, the liquid nitrogen may squirt out forcefully. Therefore observe the
following safety note to avoid frostbites:
➣
Pour the liquid nitrogen slowly in the funnel to minimize boiling and splashing.
➣
Stand clear of boiling and splashing liquid nitrogen and escaping gases. Wear
suitable protective goggles or a face shield.
➣
Be aware that liquid nitrogen can squirt out of the detector dewar from time to
time during the entire filling process.
Wait until the funnel is empty before refilling it. When the liquid nitrogen stops streaming
out, the detector dewar has cooled down to liquid nitrogen temperature. Then, pour again
some liquid nitrogen in the funnel.
Repeat this procedure until the dewar is filled to maximum. As a rough rule of thumb for
the MCT detector: the maximum capacity is about the quantity of two to three funnel fill-
ings. Note that the first two funnel fillings will evaporate almost completely at the begin-
ning.
Avoid overfilling the dewar! Otherwise the liquid nitrogen flows out.
3
After having poured in sufficient liquid nitrogen, remove the funnel and reinsert the plug in
the filling hole.
4
➣
Wait about 20 minutes before starting the first spectroscopic measurement to allow
the detector to stabilize thermally.
CAUTION