Initial Operation - Bosch GTC 400 C Professional Orginal-Betriebsanleitung

OBJ_BUCH-3136-002.book Page 19 Monday, July 24, 2017 12:07 PM
 Make sure that the measuring tool is correctly acclima-
tised. In the event of severe temperature fluctuations or
environmental conditions which vary to a large degree, the
measurement accuracy of the measuring tool may be im-
paired until it is fully acclimatised again.
 Avoid hard knocks to the measuring tool or dropping it.
After severe external influences and in the event of abnor-
malities in the functionality, you should have the measur-
ing tool checked by an authorised Bosch after-sales ser-
vice agent.

Initial Operation

Switching On and Off
To take a measurement, fold the protective cap 1 upwards.
Make sure that the infrared measuring area is not closed
off or covered while working.
To switch on the measuring tool, press the On/Off button 9.
A start sequence will appear in the display 14. After the start
sequence, the measuring tool will immediately begin to meas-
ure and will measure continuously until it is switched off.
Note: In the first few minutes, the measuring tool may self-
calibrate several times, as the sensor temperature and ambi-
ent temperature have not yet been brought into line. Perform-
ing calibration again enables precise measurement. The ther-
mal image freezes briefly during calibration.
To switch off the measuring tool, press the On/Off button
again. The measuring tool saves all settings and then switches
itself off. Close the protective cap 1 to transport the measur-
ing tool safely.
In the "Settings" menu, you can choose whether and after how
much time the measuring tool automatically switches off (see
"Switch-off time", page 21).
If the battery or the measuring tool is not within the operating
temperature range stated in the Technical Data, the measur-
ing tool will shut down automatically after a brief warning (see
"Troubleshooting – Causes and Corrective Measures",
page 22). Allow the measuring tool to reach to the correct
temperature and then switch it back on.
To save energy, only switch the measuring tool on when you
are using it.
Preparing for Measurement
Setting the Emissivity Degree for Surface-temperature
Measurements
The emissivity degree of an object depends on the material
and the structure of its surface. It indicates whether an object
(in comparison with other objects with the same tempera-
ture) emits much or little infrared heat radiation.
To determine the surface temperature, the tool performs a
contactless measurement of the natural infrared thermal radi-
ation emitted by the object at which the tool is aimed. To en-
sure correct measurement, the emissivity setting on the
measuring tool must be checked before every measure-
ment and adapted to the measuring object if necessary.
You can select one of the preset emissivity levels or enter an
exact numerical value. Adjust the required emissivity using
the "Measurement" >"Emissivity" menu (see page 21).
Bosch Power Tools
 Temperature measurements will only be correct if the
emissivity setting and the emissivity of the object
match.
Differences in colour may be caused by different tempera-
tures and/or different emissivity levels. If the emissivity levels
are very different, the depicted temperature differences may
differ considerably from the actual temperature differences.
If there are multiple objects made of different materials or
that have different structures in the measurement range, the
displayed temperature values are only conclusive for the ob-
jects that match the emissivity setting. For all other objects
(with different emissivity levels), the displayed colour differ-
ences can be used as an indication of temperature relation-
ships.
Material
Concrete
Plaster/mortar
Roofing tiles
Roofing felt
Radiator paint
Wood
Linoleum
Paper
Notes on the Measuring Conditions
Highly reflective or shiny surfaces (e.g. shiny tiles or polished
metals) may distort or impair the results shown. If necessary,
mask the surface to be measured with a dark, matt adhesive
tape that conducts heat well. Allow the tape to acclimatise
briefly on the surface.
Make sure that a favourable measuring angle is used on reflec-
tive surfaces in order to ensure that the thermal radiation re-
flected by other objects does not distort the result. For exam-
ple, the reflection of your own body heat may interfere with
the measurement when measuring head-on from a perpendic-
ular position. On a level surface, the outline and temperature
of your body could therefore be displayed (reflected value),
and these values do not correspond to the actual temperature
of the measured surface (emitted value or real value of the
surface).
Measuring through transparent materials (e.g. glass or trans-
parent plastics) is fundamentally not possible.
The accuracy and reliability of the measuring results increase
with better and more stable measuring conditions.
Infrared temperature measurement is impaired by smoke, va-
pour/high air humidity or dusty air.
Information for achieving improved measurement accuracy:
– Get as close as possible to the measuring object to mini-
mise interfering factors between you and the surface to be
measured.
– Ventilate indoor areas prior to measurement, especially
when the air is contaminated or extremely steamy.
After ventilating, allow the room to acclimatize for a while
until the usual temperature has been reached again.
English | 19
Emissivity
(reference value
0 °Cto100 °C)
0.93
0.93
0.93
0.93
0.93
0.91
0.88
0.89
1 609 92A 3RD | (24.7.17)