4. Measurement method
The PeakTech 4955 has three internal sensors for infrared-
temperature (IR), air temperature (AT) and relative humidity
(RH%) and an external temperature sensor using type-K (TK)
connection.
* The dew point (DP) is calculated from the ratio of the surface
temperature (IR) and relative humidity (RH%).
* The wet bulb temperature is calculated from the ratio of the air
temperature (AT) and relative humidity (RH%).
4.1. IR Distance to Spot size
D: Distance
S: Spot size
As “Distance to Spot size” the ratio of the distance from the
measured object to the size of the measuring surface is referred
to.
The further away you are from the target during the infrared
measurement, the bigger the Spot size will be. This can cause
that not only the desired object, but also environmental factors
are measured which can cause bad measurement results.
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