Fluke 7102 - Calibration of Multiple Probes; General Operation; Change Display Units; Bath Fluid

7102
User’s Guide
14
For best results when you calibrate over a wide temperature range, start at the lowest temperature and
progress to the highest temperature.
Use probe clamps or drill holes in the access cover to hold probes in place. Other fixtures to hold the
probes can be designed. Keep the reference probe and the probe(s) to be calibrated as closely
grouped as possible (while allowing adequate spacing for fluid to pass between the probes) in the
working area. For maximum bath stability, keep the working area covered.
To prepare for calibration:
• Place the reference probe in the bath working area.
• Place the DUT in the bath working area as close as possible to the reference probe.
Calibration of Multiple Probes
Fully loading the bath with probes increases the required probe temperature stabilization. Use the
reference probe as the guide to make sure that the temperature has stabilized before you start the
calibration.
General Operation
Change Display Units
The temperature units are factory defaulted to Celsius. To change to Fahrenheit or back to Celsius:
1. Push SET and UP simultaneously. The temperature display changes units.
2. Push SET three times to store the changes. The display shows:
Un=C
or
1. Push UP or DOWN to change units.
2. Push SET to store the changes.
Bath Fluid
Many fluids work with the Product. When you choose a fluid consider the many important
characteristics of the fluid. Among these are temperature range, viscosity, specific heat, thermal
conductivity, thermal expansion, electrical resistivity, fluid lifetime, safety, and cost. The next sections
explain each of these characteristics in detail.
Temperature Range
An important characteristic to consider is the temperature range of the fluid. Few fluids work well
throughout the complete temperature range of the bath. The bath operating temperature must always
be within the safe and useful temperature range of the fluid. The freeze point of the fluid or the
temperature at which the viscosity becomes too great determines the lower temperature range of the
fluid. The upper temperature is usually limited by vaporization, flammability, or chemical breakdown of
the fluid. Vaporization of the fluid at higher temperatures can affect temperature stability because of
cool condensed fluid that drips into the bath from the lid.