LaserLiner MultiTest-Master Manual page 10

7 Illuminance (lux)
A photoelectric sensor is used to measure the incident light intensity.
This is the power of the radiated light per unit of area. Photometry
de nes light in terms of how it is perceived by the human eye. The
sensitivity of the eye also depends on the wavelength or light colour.
The measuring unit uses special colour lters on the sensor that
adapt to the sensitivity curve (CIE curve).
After switching on the device, press the „Lux" button.
Please observe the following application notices when
determining illuminance:
– Align the sensor on the measuring surface so it is perpendicular to
the light source
– During measurement, the incidence of light must not be affected
by shadows from the operator or other objects not involved in the
measurement
– Remove the wind de ector from the microphone
– You can check the measuring device's zero position by covering the
sensor completely.
– Discharge, uorescent or energy-saving lamps should be switched
on well in advance of the measurement process (approximately 15
minutes) so that the brightness has time to stabilise
By pressing the „Mode" button, you can get the device to display the
highest (MAX), lowest (MIN), average (AVG) or difference value (DIF)
in addition to the current measured value. As its name suggests, the
„HOLD" button enables you to hold the current measured value.
!
The device measures radiation in the main direction, perpendicular to the sensor plane. Incident
light rays at an angle are taken into account by the sensor using an adjustment curve.
Reference values for illuminance in indoor spaces
Practical example
Traf c areas, ancillary rooms
Corridors in buildings used by people
Sanitary facilities, machine rooms, staircases
Regularly occupied work stations within production facilities, canteens
Conference rooms, gyms
Of ces, medical facilities (emergency unit)
Design and drawing rooms
Monitoring locations, assembly rooms, test stations
Assembly rooms for small components
The amount of light available in outdoor spaces is approximately 100
times greater than in indoor spaces. In the event of a high incidence
of light, the measured value on the display is reduced by a factor of
10 or a factor of 100.
10 GB
SET
TEMP/%RH
MODE MODE
dB
UNIT HOLD
SET
TEMP/%RH
MODE MODE
dB
UNIT HOLD
Luminous intensity in lux
20
50
100
200
300
500
750
1000
1500