General Tools and Instruments VR40 - Manual (Page 21)

• If the temperature of the IRT’s target is lower than
-4°F (-20°C)—the lower limit of the unit’s
measurement range—“LO” will appear on the
readout.
• If the temperature of the IRT’s target is higher than
626°F (330°C)—the upper limit of the unit’s
measurement range—“HI” will appear on the
readout.
• The IRT cannot make accurate measurements if there
is glass or plastic between it and the target.
• Clean the lens of the infrared sensor (Fig. 1, Callout 9)
often—but never use a solvent.
• Abrupt temperature changes will cause condensation
and possible vapor penetration. Clean the LCD after
the vapor evaporates. Blow off loose particles with
clean, compressed air. Gently brush remaining debris
away with a lens hair brush.
• To clean the housing, use a moist cotton swab or wet
sponge. Avoid excessive amounts of water and
corrosive gas or liquids.
• Remove the batteries if you don’t expect to use the
VR40 for an extended period of time (months or
years).
• Do not drop or disassemble the instrument or
immerse it in water.
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