Advanced Instruments 3320, User Manual

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Advanced ® Micro-Osmometer Model 3320 User’s Guide
Troubleshooting checks
Check operational requirements. If you are experiencing difficulties
with your instrument, first carefully review the operational requirements
listed in the product specifications and the recommended setup and
operating procedures.
Check fuses. You will find the power switch and fuse holder beside
the power cord connector on the back panel of the instrument. Switch
the power switch to the off position and disconnect the power cord.
Use a small flat-bladed screwdriver or similar tool to remove the fuse
holder. Visually check for a blown fuse. If there is any doubt, test the
fuses with a continuity checker or ohmmeter or simply replace them
with new fuses.
Check error messages. The software of your instrument is designed
in such a way that any incomplete task will be associated with an error
message, many self-explanatory, that will help you discover the source
of your problem. You can find all error messages and descriptions of
what they mean in Appendix A.
Using the Diagnostics menu
The Diagnostics Menu [DIAG] contains items that allow discrete test-
ing of each component of the instrument. Enter the Diagnostics Menu
by scrolling to it, and pushing the
[DIAG]
button. A description of the
available tests follows.
1. A/D Tests
A/D Tests are designed to check the performance of the cooling
assembly, and the efficiency of heat transfer between the compo-
nents of the cooling assembly. The result of an A/D Test gives a
"duty cycle", expressed as a percentage indication of how much
power the thermoelectric cooler uses to reach an operating tempera-
ture sensed by the block probe. An increasing duty cycle indicates
deteriorating performance of the cooling assembly. Pressing the left
button will change the set or selected cooling assembly temperature.
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