testo 830-T4 Manual De Instrucciones página 13

9.2 Clean instrument
Do not use abrasive cleaning agents or solutions.
► Clean the housing with a damp cloth (soap water).
► Carefully clean the lens with water or cotton buds dipped in
water or medical alcohol.
10. Questions and Answers
Query
Display is no longer illuminated — Low battery.
lights up..
Instrument cannot be switched
on
Infrared measurement mode:
- - - lights up.
Contact measurement mode:
- - - lights up.
If we have not answered your question, please contact your local
distributor or testo´s Customer Service.
11. Information on infrared measurement
11.1 Measurement method
Infrared measurement is an optical measurement
► Keep lens clean.
► Do not measure with clouded lens.
► Keep­measurement­field­(area­between­instrument­and­object­
being measured) free of interferences: no dust and dirt particles,
no moisture (rain, steam) or gases.
Infrared measurement is a surface measurement
If there is dirt, dust, frost etc. on the surface, only the top layer will
be measured, i.e. the dirt.
► In the case of shrinkwrapped foodstuffs, do not measure in
air pockets.
► If values are critical, always subsequently measure using a
contact thermometer. Particularly in the food sector, the core
temperature should be measured with a penetration/immer­
sion thermometer.
Adaptation time
► If the ambient temperature changes (change of location, e.g.
inside / outside measurement) the instrument needs an adap­
tation time of 15 minutes for infrared measurement.
Possible causes
— Battery empty.
— Battery empty.
— Readings outside
measurement range.
— Readings outside
measurement range.
— No probe connected.
— Probe damaged.
Possible solution
► Change battery.
► Change battery.
► Change battery.
—
—
► Connect probe.
► Change probe.
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