Maintenance - Extech Instruments 42580 User Manual

Maintenance

Cleaning
Wipe instrument with damp cloth as needed. Do not apply solvents or abrasives to the
meter. Store in a cool dry place with the batteries removed.
Battery Replacement
When the batteries weaken, the LCD display will dim or go completely blank. To replace
the batteries, open the rear battery compartment and insert four (4) new 1.5V 'AA' batteries
with correct polarity position.
Paper roll replacement
When the paper roll is depleted, flip up the
paper compartment, drop in a new roll, and
feed the paper using the LF button. New paper
rolls are available through Extech instruments
and Extech distributors.
Emissivity Considerations
The amount of IR energy emitted by an object is proportional to an object's temperature and
its ability to emit energy. This ability is known as emissivity and is based upon the material of
the object and its surface finish. Emissivity values range from 0.1 for a very reflective object
to 1.00 for a flat black finish. The 42580 senses IR energy and calculates the temperature
based upon the amount of IR energy it receives using a factory default emissivity setting of
0.95 (this setting covers 90% of applications).
Most organic materials and painted or oxidized surfaces have an emissivity factor of 0.95.
Inaccurate readings will result from measuring shiny or polished metal surfaces which have
emissivity factors other than 0.95. To compensate for polished/shiny surfaces, cover the
surface with masking tape or flat black paint. Allow time, before measuring, for the tape to
reach the same temperature as the material underneath it.
Emissivity Factors for Common Materials
Material under test
Asphalt
Concrete
Cement
Sand
Soil
Water
Ice
Snow
Glass
Ceramic
Marble
Plaster
Mortar
Brick
Emissivity Material under test
0.90 to 0.98 Cloth (black)
0.94 Skin (human)
0.96 Lather
0.90 Charcoal (powder)
0.92 to 0.96 Lacquer
0.92 to 0.96 Lacquer (matt)
0.96 to 0.98 Rubber (black)
0.83 Plastic
0.90 to 0.95 Timber
0.90 to 0.94 Paper
0.94 Chromium Oxides
0.80 to 0.90 Copper Oxides
0.89 to 0.91 Iron Oxides
0.93 to 0.96 Textiles
9
Emissivity
0.98
0.98
0.75 to 0.80
0.96
0.80 to 0.95
0.97
0.94
0.85 to 0.95
0.90
0.70 to 0.94
0.81
0.78
0.78 to 0.82
0.90
Model 42580 Version 2.2 11/03