Agilent InfinityLab LC Series Vialsamplers User Manual
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6
Troubleshooting and Diagnostics
Diagnostic Tests
Diagnostic Tests
Sample Cooler Function Test
The
Sample Cooler Function Test
is a diagnostic test to verify the correct
functioning of the Sample Cooler/Sample Thermostat. The test takes up to
15 min to complete and returns a pass/fail type result. If the test failed or was
aborted by the system, the final report will include some information on the
possible root causes.
Before the test starts, the compressor is turned off to allow the system to reach
the initial conditions. The test starts with acquiring data from the evaporator
temperature sensor. If the reading is stable for at least 10 s (
Δ
T < 0.5 °C), the
compressor turns on and the temperature inside the cooler/thermostat starts to
drop.
For the test to succeed, the system must pass three temperature checkpoints in
a timely manner. These checkpoints are the following:
•
Checkpoint 1: The temperature drops by 1/3 of the difference between the
starting temperature and 5 °C.
•
Checkpoint 2: The temperature drops below 5 °C.
•
Checkpoint 3: The temperature stabilizes at a value below 5 °C and stays
stable for at least 60 s (
Δ
T < 1.0 °C).
For a Sample Thermostat, the heater resistance of the heating elements will also
be tested and checked if the measured value is within the acceptance range
(5 – 9 Ohm).
NOTE
For testing the heater resistance of the Sample Thermostat, Lab Advisor version
B.02.11 or higher is needed.