General Tools and Instruments IRT653 - Manual (Page 5)

EMISSIVITY:
Emissivity is the ability of an object to omit or absorb energy.
Perfect emitters have an emissivity of 1, emitting 100% of
incident energy.
An object with an emissivity of 0.8 will absorb 80% and
reflect 20% of the incident energy. Emissivity is defined as
the ratio of the energy radiated by an object at a given
temperature to the energy emitted by a perfect radiator at
the same temperature. All values of emissivity fall between
0.0 and 1.0.
Non-contact temperature sensors measure IR energy emitted
by the target, have fast response, and are commonly used to
measure moving and intermittent targets, targets in a
vacuum, and targets that inaccessible due to hostile
environments, geometry limitations, or safety hazard.
The cost is relatively higher, although in some cases it is
comparable to contact devises.
MAINTENANCE:
Cleaning the lens: Blow off loose particles using clean
compressed air. Gently brush remaining debris away with a
camel’s hair brush. Carefully wipe the surface with a moist
cotton swab. The swab may be moistened with water.
NOTE: DO NOT use solvents to clean the lens.
CLEANING THE HOUSING: Use soap and water on a damp
sponge or soft cloth.
EMISSIVITY TABLE
Material
Temp °F/°C Emissivity
Gold (pure highly polished) 227/440 0.02
Aluminum Foil 27/81 0.04
Aluminum Disc 27/81 0.18
Aluminum Household(flat) 23/73 0.01
Aluminum(polished prate 98.3%) 227/400 0.04
577/1070 0.06
Aluminum (rough plate) 26/78 0.06
Aluminum (oxidized @ 599°C) 199/390 0.11
599/1110 0.19
Aluminum surfaced roofing 38/100 0.22
Tin(bright tinned iron sheet) 25/77 0.04
Material Temp °F/°C Emissivity
Nickel wire 187/368 0.1
Lead (pure 99.95-unoxidized) 127/260 0.06
Copper 199/390 0.18
599/1110 0.19
Steel 199/390 0.52
599/1110 0.57
Zinc galvanized sheet iron (bright) 28/82 0.23
Brass (highly polished) 247/476 0.03
Brass (hard rolled-polished w/lines) 21/70 0.04
Iron galvanized (bright) - 0.13
Iron plate (completely) 20/68 0.69
Rolled sheet steel 21/71 0.66
Oxidized iron 100/212 0.74
Wrought iron 21/70 0.94
Molten iron 1299-1399/ 0.29
3270-2550
Copper (polished) 21-117/70-242 0.02
Copper (scraped shiny not mirrored) 22/72 0.07
Cooper (plate heavily oxidized) 25/77 0.78
Enamel (white fused on iron) 19/66 0.9
Formica 27/81 0.94
Frozen oil - 0.93
Brick (red-rough) 21/70 0.93
Brick (silica-unglazed rough) 1000/1832 0.8
Carbon (T-carbon 0.9% ash) 127/260 0.81
Concrete - 0.94
Glass (smooth) 22/72 0.94
Granite (polished) 21/70 0.85
Ice 0/32 0.97
Marble (light gray polished) 22/72 0.93
Asbestos board 23/74 0.96
Asbestos paper 38/100 0.93
371/700 0.95
Asphalt (paving) 4/39 0.97
IRT653 Manual -2P-043008:Layout 1 4/30/08 12:29 PM Page 5