Raynger 3i Series Operator's Manual Glossary-1
Absolute Zero
The temperature (0 Kelvin) of an object
defined by the theoretical condition where the
object has zero energy.
Accuracy
Maximum deviation, expressed in tempera-
ture units, or as a percentage of the tempera-
ture reading, or as a percentage of the full
scale temperature value, or as a percentage of
the target temperature, indicating the differ-
ence between a temperature reading given by
an instrument under ideal operating condi-
tions, and the temperature of a calibration
source (per the ASTM standard test method E
1256-88).
Activate
Pressing the activate button (available on vari-
ous units) while in different modes can acti-
vate alarms and TAM, or toggle between digi-
tal and analog outputs or between °C and °F.
Ambient Derating
Refer to Temperature Coefficient.
Ambient Operating Range
Range of the ambient temperature conditions
over which the thermometer is designed to
operate.
Ambient Temperature
Room temperature or temperature surround-
ing the instrument.
Ambient Temperature Compensation (TAMB)
Refer to Reflected Energy Compensation.
ASTM
American Society for Testing and Materials.
Atmospheric Windows
Infrared spectral bands in which the atmos-
phere best transmits radiant energy. Two pre-
dominant windows are located at 2-5 µm and
at 8-14 µm.
AVG
Average. Units with this feature have the abil-
ity to display the average of measured temper-
atures. AVG is a weighted average of all read-
ings taken since the trigger was pulled.
Background Temperature
Temperature behind and surrounding the
target, as viewed from the instrument.
Blackbody
A perfect emitter; an object that absorbs all
the radiant energy incident on it at all wave-
lengths and reflects and transmits none. A
surface with emissivity of unity (1.00).
°C (Celsius)
Temperature scale based on 0° (zero degrees)
as the freezing point of water, and 100° as
the vaporization point of water, at standard
pressure. °C = (°F - 32) ÷ 1.8.
Calibration
A methodical measurement procedure to
determine all the parameters significantly
affecting an instrument’s performance.
Calibration Source
A source (blackbody, hot plate, etc.) of
known and traceable temperature and emis-
sivity. Usually NIST traceable in the USA,
with other recognized standards available
for international customers.
Colored Body
See Non-Gray Body.
D:SDistance to size ratio. See Optical
Resolution.
Detector
Transducer which produces a voltage or cur-
rent proportional to the IR energy incident
upon it. See also thermopile, pyroelectric,
and Si detectors.
Dielectric Withstand Voltage
(Breakdown Voltage)
The voltage up to which a dielectric (insula-
tor) can endure before conduction through
the material occurs.
DIFDifferential. When this mode is activated,
the difference between the temperatures of
the last series of measured temperatures dis-
plays.
Glossary Of Terms