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Anemometer
(PosiTector DPM-A probes only)
When Enabled, the PosiTector DPM A will display wind velocity (v) in the selected unit
of measure.
NOTE:
Dew point (Td) and surface temperature (Ts) are not displayed when the Anemometer
is enabled.
Emissivity
(PosiTector DPM-IR probes only)
Sets the emissivity ratio for the PosiTector DPM-IR infrared temperature sensor.
Emissivity refers to a material’s ability to emit infrared energy, compared to an ideal
black surface at the same temperature. The ratio varies from 0 to 1, and each material
has a specific emissivity associated with it. The PosiTector DPM-IR has built in
emissivity settings for certain materials as well as a user-adjustable emissivity option.
Most organic and painted surfaces have an emissivity of around 0.95, and are ideal
surfaces for accurate infrared temperature readings. Shiny or reflective surfaces can be
difficult to measure with an infrared thermometer, as they tend to reflect ambient
infrared energy instead of their own. To compensate for this, cover such surfaces with
flat paint or a piece of electrical tape. Allow the paint or tape to acclimate to the
surface’s temperature, and take a measurement over the paint or tape.
Select Custom to manually adjust the emissivity value or to adjust to a known
temperature. Emissivity is automatically calculated when adjusting to a temperature.
See NOTE below.
Alternatively, use one of the following preset options:
Aluminum (rough) = 0.07
Plastics = 0.94
Zinc (Galvanized) = 0.25
Steel (Oxidized) = 0.95
Concrete = 0.54
Wood = 0.95
Paint = 0.96
NOTE:
Depending on surface treatment, metals such as blasted steel can have a broad range
of emissivity values. Adjusting to a known temperature (measured by a direct contact
surface temperature probe) on a representative sample will assist in obtaining an
