Velleman DVM8838, Руководство пользователя

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DVM8838
00 (23/10/2008) 5 Velleman
®
•
Note that MAX, MIN, DIF and AVG only apply to the current measuring session (time
between pulling the trigger
[8] and releasing it). Their value is reset when an new
measurement starts or the thermometer switches off.
•
To switch between measurements in °C and °F, open the battery cover [10] . The battery
cover has a hinge at the bottom of the device. Hold the battery cover at the top (next to
the measurement trigger
[8] ) and gently pull away from the device.
•
The °C/°F switch [K] is located just below the measurement trigger [8] . Move this switch
to the desired setting. The current setting is indicated [F] in the display.
•
Also under the battery cover [10] , there is a lock switch [L] . Move this switch to the ON-
position for continuous measurement. The current setting is indicated with a lock symbol
[D] in the display. Start measuring by pulling the measurement trigger [8] once. Consider
disabling the laser targeting beam in continuous measuring mode to save battery power. To
stop and disable lock mode, set the switch
[L] back to the OFF-position. In lock mode, it is
still possible to adjust EMS, HAL and LAL values.
•
The third switch under the battery cover [10] is the alarm set switch [M] . Move this switch
to the ON-position to enable alarm warnings when high or low alarm limits are exceeded.
When enabled, a Hi- and LOW indication
[G] are shown on the display.
•
Close the battery cover [10] by pushing it back towards the device until it snaps in place.
•
When the measured value exceeds a preset alarm limit, an audible alarm signal will be
produced (when the alarm set switch
[M] is set to ON ), and the according alarm icon in the
display [G] will flash. Alarm will stop when temperature is back within preset limits.
•
Push the laser/backlight button [7] to cycle through the laser and backlight options. Note
that the laser beam is only an aiming aid, be careful when using it . Refer to the safety
instructions .
Push result display
1 backlight on indicator [E]
2 backlight on and laser enabled indicator [E] + [D]
3 backlight off and laser enabled indicator [D]
4 backlight off and laser disabled no indication
Notes:
•
The device powers off automatically (after ± 7 seconds) when no activity is detected,
unless it is in lock mode.
•
The unit will not measure correctly through transparent surfaces (e.g. glass), as it will
measure the surface temperature of the transparent surface.
•
Steam, dust, smoke etc. will have a negative impact on the measurements accuracy.
•
Measurements on shiny and/or polished surfaces are not recommended.
7.
Useful information
Working principle
The Infra Red sensor of the unit detects energy that is emitted, reflected and transmitted by
a surface. This energy is focussed onto a detector that converts this information into a
temperature reading. The laser beam is only used for aiming purposes.
Ambient temperature
The thermometer automatically compensates ambient temperature conditions. Allow the
thermometer to stabilise to ambient temperature for at least 30 minutes for accurate
measurements.
Surface temperature
When going from low temperature to high temperature measurements or vice versa, the IR
sensor of the thermometer needs a few minutes to adjust.
Distance and spot size
Refer to the drawing on page 2 of this manual.
As the distance (D) from the object increases, the spot size (S) of the area measured by the
unit becomes larger. The focal point for this unit is 914mm (36”). Note that the laser beam
points 16mm above the measurement centre point.