Hach Lachat QuikChem, Руководство пользователя

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Figure 8 Tubing replacement on the heater block
Troubleshooting
C A U T I O N
Burn hazard. Obey safe handling protocols during contact with hot
sample components.
Decrease the temperature on the instrument to 70 ºC (158 ºF) or less
before the pump tubes are examined. The typical amount of time to
decrease the temperature from 140 ºC (284 ºF) to 70 ºC (158 ºF) is
approximately 10 minutes.
General troubleshooting considerations
The in-line manifolds are different than the standard FIA manifolds. The
main differences are:
• Sample line—The sample line used is usually not a green-green pump
tube. Smaller pump tubes are chosen so that the sample (mixed with
a digestion solution) is put on the heater and on the UV lamp for a
longer period of time.
• Pre-valve sample preparation—The sample line from the sampler
does not go directly to Port 6 of the injection valve. The sample line
mixes with a digestion solution, gets heated, gets UV irradiated, then
goes through the diffusion block or bubble tap membrane, and travels
to Port 6 of the injection valve.
Table 3 shows the most common problems encountered:
Table 3 Troubleshooting guide
Problem Solution
Air spikes in the FIAgram Make sure that the timings agree with the
information in
Find the correct timing
on page 11.
Do a degass procedure on the reagents.
Replace the membrane in the dialysis block or
replace the bubble trap membrane.
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