Thermo Scientific Oretronic III, Руководство по эксплуатации и обслуживанию

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Maintaining & Troubleshooting
Thermo Fisher Scientific Maintaining & Troubleshooting 4-3
REC-4105 Rev L
When you calibrate the TMD during initial setup, the microprocessor
“imprints” the signal level produced by the piece of tramp metal you use
for the calibration. The TMD then trips when tramp producing that
signal level or greater passes through the detector.
However, setup and calibration were done with the conveyor belt
stopped or running empty. Because background noise caused by
material may be different with the belt running loaded, you should
observe the TMD for a day or two before changing the device setup or
calibration settings.
There are two basic types of problems you could be having with the
TMD: false tripping or passing tramp undetected. Both of these
problems are costly. False trips stop the conveyor and interrupt the
process flow. Undetected tramp damages process machinery.
Common reasons for false tripping include:
• Coil
imbalance
• Sensitivity set too high
• Improper bar/rod detection
• Improper clip (belt splice) detection
Common reasons for passing tramp undetected include:
• Sensitivity set too low
• Tramp is too small
• Coil
damage
• Detector malfunction
The remainder of this chapter describes the diagnostic processes for
these problems and offers suggestions for correcting them.
Diagnosing and
Correcting
Problems