User manual

21
4. QUANTUM LIGHT METER
4.1 Technical Specifications
TECHNICAL SPECIFICATIONS:
Measurement range: 0 – 1,999 µmol/m²s
Measurement precision: ± 5%
Display: Liquid crystal display
Operating temperature: 0 to + 50 °C
Humidity range: < 80% air humidity
Power supply: 9-Volt battery, 6LR61 size
Dimensions and weight:
75 x 150 x 27 mm (W x H x D), 130 g
Figure 4:
Components of the
QUANTUM LIGHT METER
4.2 Operating Instructions
Operating the meter
1. Turn the dial to the “ON” position.
2. Hold the meter vertically so that the sensor is
in a precisely level position at the top of the
meter.
3. Hold the meter at the height of your eyes so
that you minimize the chance of shade from
your body.
4. The display show the photosynthetic photon
flow (PPFD) where the unit is µmol/m
2
s.
5. Turn off the Quantum meter after you are
done using it.
Battery replacement
The QUANTUM LIGHT METER requires
a standard 9-volt battery (6LR61). Un-
screw the two screws on the back of
the meter before changing the battery.
Detach the rear section of the housing from
the front section. Remove the old battery
from the connection and connect the new
battery in place. Insert the battery into the
front side of the meter. Push down on the
rear section in order to reattach it to the front
section of the meter. Tighten the two screws
into the housing.
Description
The QUANTUM LIGHT METER can be used
to calculate the photon flux density (PPFD)
that is relevant to plant growth. The PPFD is
in µmol/m
2
s (Compare to 5.3); it can be de-
termined from sun light, from artificial light
sources (refer to page 32), or from mixed-
source lighting.
The sensitivity distribution, in relation to the
wavelength of the light (refer to Figure 5), is
significantly “wider” than a LUX METER/
LIGHT METER (Fig. 1, page 51).
Thus the analysis for sunlight is the same as
that for the high-pressure sodium-vapour
lamps used in green houses. The display
must be corrected by a factor of slightly less
than 1 for other artificial light sources.