Bartec R3 Series User Manual

Annex
A - 69
Operating Instructions Radiation sensors R3XX
Annex
Emission factor
If you want to measure the temperature of an object without contact, you
need to know the emission degree “E” and include it in the measurements.
The calibration basis for IR temperature measuring units and control units is
the black body with the emission degree E = 1.
Determining the actual E factor
The emission factor depends on the material and the condition of its surface.
Theoretical values are specified in the corresponding literature.
Due to the fact that the E factor also depends on the wavelength, the
temperature and the direction in which the radiation is emitted, however, the
values listed in the table can only be used as rough approximates, for
instance for project planning. It can generally be said that raw, matt or
oxidized surfaces have a higher E factor than shiny materials.
Table showing the emission factor E at room temperature
Surface
Temperature (°C)
E factor
Asbestos slate
Bakelite varnish
Lead, oxidized
Chrome nickel, oxidized 20 Ni 25 Cr 55 Fe
Chrome nickel, oxidized 20 Ni 25 Cr
Chrome nickel, oxidized 60 Ni 12 Cr 28 Fe
Roofing felt
Ice, smooth, water layer
Ice, rough surface
Enamel, white / porcelain
Iron, oxidized
Iron, oxidized
Iron, rusty
Iron, rolling skin
Plaster
Glass
Graphite
Rubber, soft, grey
Rubber, hard
Skin, dry
Radiator varnish, oil paint
Wood (beech)
Plastics (PVC, PTFE, PE at thicknesses of 0.4 mm
or more)
Copper, oxidized
Matt varnish, e.g. 3 M 1020
Brass, oxidized
Paper
Steel, raw
Clay, baked
Brick, mortar, plaster
20
80
200
200
500
270
20
0
0
20
100
500
25
20
20
20...90
20
25
25
30
85
20...70
20...150
20...130
20...120
200...600
20
40...400
70
20
0.93
0.935
0.63
0.90
0.97
0.89
0.93
0.966
0.985
0.9...0.92
0.74
0.84
0.85
0.77
0.85
0.94
0.45
0.86...0.94
0.955
0.96
0.925
0.915
0.91
0.77
0.96
0.60
0.85
0.79...0.94
0.91
0.93

Bartec R3 Series Specifications

General

Brand	Bartec
Model	R3 Series
Category	Accessories
Language	English