UP–Usedtoincrementthedisplayedvalue.
EXIT – Used to exitfrom a menu. When EXIT is pressed any changes made to
the displayedvalue will be ignored.
ControlIndicator - The Control In dicator is a twoco lor light emitting diode.
This indicator lets the user visually see the ratio of heating to cooling. When
the indicatoris constant red the well is heating, and when it is constant green
the wellis cooling. When the indicator is flashing then the temperature is being
held constant.
6.3 Constant TemperatureBlock Assembly
6.3.1 Constant TemperatureBlock
The block, Figure4 , ismade of aluminumand provides a relatively constant
and accurate temperature environmentin which the sensors that are to be cali-
brated are inserted.The .75 inch diameter holein the center of the block may
be used for sensorsof that size or sleeved down with various sized probe
sleeves.The block also has 4 smaller holes of various sizes. Attached to the
block are Peltier thermoelectric modules which heat or cool theb lock to main-
tain a constant temperature. A high-quality platinum RTD isimb edded in the
block to sense the temperatureand p rovidefeedback to the temperature control-
ler.
6.3.2 Probe Sleeves and Tongs
Probe sleevesof various internal hole sizes are available to allow the user's
probe to fitsnugly into the well whatever the diameter of the probe.
9105/9107 17
6Parts and Controls
3/4"O.D. Aluminum Insert
3/16"Well 1/4"Well
1/4"Well 1/8"Well
Figure4 Welland Insert