Notes - Waeco ST-8810 Instrucciones De Uso

_ST-8810.book Seite 16 Donnerstag, 2. Februar 2006 11:24 11

Notes

5 Notes
How it works
Infrared thermometers measure the surface temperature of an object. The
meter's optics sense emitted, reflected and transmitted energy, which is
collected and focused onto a detector. The meter's electronics translate the
information into a temperature reading which is indicated on the display. In
meters with a laser, the laser is used for aiming purposes only.
Field of view
Make sure that the target is larger than the unit's spot size. The smaller the
target, the closer you should be to it. If accuracy is critical, make sure the tar-
get is at least twice as large as the spot size.
Distance and spot size
When the distance from the object increases, the spot size of the area
measured by the meter becomes larger (Fig. 1).
Locating a hot spot
To find a hot spot aim the thermometer outside the area of interest, then scan
across the area of interest with an up and down motion until you locate the
hot spot.
Reminders
The meter is not recommended for measuring shiny or polished metal
surfaces such as stainless steel, aluminium, etc. (see "Emissivity").
The meter cannot measure through transparent surfaces such as glass.
It will measure the surface temperature of the glass instead.
Steam, dust, smoke, etc., can prevent accurate measurement by ob-
structing the meter's optics.
Emissivity
Most organic materials and painted or oxidized surfaces (90% of typical
applications) have an emissivity of 0.95 (pre-set in the unit). Inaccurate read-
ings will result from measuring shiny or polished metal surfaces. To compen-
sate cover the surface to be measured with masking tape or flat black paint.
Allow some time for the tape to reach the same temperature as the material
underneath it. Measure the temperature of the tape or painted surface.
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ST-8810