Thermosense HL-800K, User Manual

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HL-800K Infrared Laser Thermometer User Manual
Thermosense Limited T: +44 (0)1628 531166 E: sales@thermosense.co.uk W: www.thermosense.co.uk
Page 8

Distance & Spot Size
As the distance (D) from the object increases, the spot size (S) of the area measured by the unit
becomes larger. See:
Fig: 1 .

Locating a Hot Spot
To find a hot spot aim the thermometer outside the area of interest, then scan across with an up
and down motion until you locate hot spot.

Reminders
1)
Not recommended for use in measuring shiny or polished metal surfaces (stainless steel,
aluminum, etc.).See Emissivity
2)
The unit cannot measure through transparent surfaces such as glass. It will measure the
surface temperature of the glass instead.
3)
Steam, dust, smoke, etc., Can prevent accurate measurement by obstructing the unit’s optics.

Emissivity
Emissivity is a term used to describe the energy-emitting characteristics of materials.
Most (90% of typical applications) organic materials and painted or oxidized surfaces have an
emissivity of 0.95 (pre-set in the unit). Inaccurate readings will result from measuring shiny or
polished metal surfaces. To compensate, cove the surface to be measured with masking tape or
flat black paint. Allow time for the tape to reach the same temperature as the material underneath
it. Measure the temperature of the tape or painted surface.
Emissivity Values
Substance Thermal emissivity Substance Thermal emissivity
Asphalt 0.90 to 0.98 Cloth (black) 0.98
Concrete 0.94 Human skin 0.98
Cement 0.96 Lather 0.75 to 0.80
Sand 0.90 Charcoal (powder) 0.96
Earth 0.92 to 0.96 Lacquer 0.80 to 0.95
Water 0.92 to 0.96 Lacquer (matt) 0.97
Ice 0.96 to 0.98 Rubber (black) 0.94
Snow 0.83 Plastic 0.85 to 0.95
Glass 0.90 to 0.95 Timber 0.90
Ceramic 0.90 to 0.94 Paper 0.70 to 0.94
Marble 0.94 Chromium oxides 0.81
Plaster 0.80 to 0.90 Copper oxides 0.78
Mortar 0.89 to 0.91 Iron oxides 0.78 to 0.82
Brick 0.93 to 0.96 Textiles 0.90
MAINTENANCE & CLEANING
 Repairs or servicing aren’t covered in this manual and should only be performed by qualified personnel.
 Periodically wipe the case with a dry cloth. Don’t use abrasives or solvents on this instrument.

When servicing, use only specified replacement parts.