8
4. Allow sufcient time for the sensor to reach temperature.
5. Use the same time base for similar type sensors. Sensors that are produced to take true
surface temperature readings are designed to minimize the heat that is pulled from the
measurement surface and should be tested at a reasonable interval; if the intended use is
for 15 to 30 seconds, do not leave the sensor on the block for 60 seconds or more to get a
better reading.
6. For the highest accuracies, it is recommended that a secondary, independent reference is
used in concert with the reference on the STS. This includes the EDL Reference System as
well as a PRT. This will allow you the periodically calibrate the sensor to help minimize
errors, and give you better traceability. For more information, see Secondary Reference
Points below.
7. Keep the surface of the block as clean and free from oxidation as possible, by cleaning as
required with 600-grit emery cloth sandpaper. Always sand the surface with the power
off and the block at room temperature.
8. If the surface becomes badly dented, resurfacing may be required. Contact EDL Service
team
for
assistance
with
sending
the
STS
in
for
servicing.
Email
[email protected] or
call
800.432.5335.
9. Never twist, drag, or slide a sensor on the surface.
Secondary Reference Points
There are unavoidable variables in all types of temperature measurements but especially in surface
measurements. Timing is critical for surface measurements because the surface of the Block is
always in a dynamic state. The surface being measured is also inuenced by the UUT, its physical
parameters, and the environment.
A secondary independent, calibrated reference instrument is strongly recommended for more
accurate surface measurements. This is accomplished by connecting a second lab calibrated
pyrometer to the Thermocouple Output on the rear panel. This moves your reference comparison
directly to the internal surface sensor, bypassing the Controller. If your expected tolerance is large,
you can use the PV display on the Controller as the reference reading but you must apply the
appropriate uncertainty as shown in Uncertainties on Page 09.
When an STS is purchased as a full Reference System, it will include the additional calibrated
reference surface sensor, pyrometer, and lead necessary for adding this secondary reference.
Additionally, the Block may be drilled to accommodate a PRT sensor connected to a secondary
independent reference instrument. The STS-SC1, STS-SC2 and STS-COOL may be ordered drilled to
accommodate a sensor 0.125” in diameter; the STS-SC2-4 comes drilled to accommodate a sensor
0.1875” in diameter. PRTs are not included.
Note:The comparison should be made to the Block temperature, prior to applying the sensor to the
surface of the Block, and the UUT reading after stabilization.
