Kaye LTR -90, Operating Manual

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Chapter 5. General Operation
22 Kaye LTR -90 Operating Manual
5.4 Probe Insertion and Removal Procedure
CAUTION! To prevent possible damage to probes, make sure all probes put into the furnace are
rated for the temperature range used in the calibration procedure.
Note:
Use a metal or ceramic fiber surface or container to set hot probes on.
A solid (unstirred) mass, as in a furnace, can have heat loss through the probe stem. The loss changes between
probes and temperatures.
For the best stable temperature and minimum gradient, put sample probes into the full depth of the well. Variation on
equipment, probe dimension, and configuration can have an effect on temperature stability and gradients. At higher
temperatures, temperature stability and gradients between test wells are equivalent. But the length of time for the wells
to become stable is much longer.
The calibrator unit is designed to be used with the rubber insulator at all times. Specifically at lower temperatures, the
insulator prevents frost buildup between the probes and the well.
Carefully insert the probes and sensors through the insulator holes, then continue into the well holes. After the sensors
are immersed into the well fully, place the plug into the hole. That will push the sensors into the three small openings
on the side, sealing the holes.
Make sure the unused holes are covered with the plugs.
Temperature changes at lower temperatures are slow. This is because high integration values are necessary to keep the
controller stable (1,200 seconds) at the lower temperatures.