Product Manual
Turf-Tec International Daylight Indicator – Light Meter - Copyright 2013
Page 3 - www.turf-tec.com
Where to Measure?
Use a “Control”
Use the Daylight Indicator to measure the
location of primary interest—on a
greenhouse bench, or on a shaded green or
tee box at a golf course. Use can also use it
as a “control” - let it receive the maximum
light, either outside your greenhouse, or in
full sun, far from the trees.
In a Greenhouse
Place Daylight Indicator where you can
compare light levels and DLI (Daily Light
Integral) with and without hanging plants and shades. Use pots with soil or media to hold the
Daylight Indicator upright. Place the Daylight Indicator outside to measure transmission loss
through the structure.
Shaded Tees, Sports Stadiums and Greens
Use the Daylight Indicator to compare the light received by healthy and stressed areas of tees,
stadiums and greens. By placing unit in the stressed area, followed by a healthy area, and then
nearby with full sun, areas of destructive shade can be documented, and the minimum light level
necessary can be determined.
In the Crop Canopy
To measure the incident light and/or DLI at, in, or below the crop canopy, secure the Daylight
Indicator at the proper location and height. For low plants, this can be as simple as inserting the
spike into the ground or into a container filled with soil or media. For taller crops, set a plastic or
metal pipe into the ground, and slip the Daylight Indicator spike into the top to hold it at the
desired height.
Using the Daylight Indicator
Place the Daylight Indicator in the ground at the desired location for evaluating
the amount of available sunlight. In a greenhouse insert the meter into a container of
similar size (containing substrate only) to that of the crop being grown, so that the meter
receives the same amount of light at the same height as the growing crop. Ensure
that the face of the unit is generally parallel to the ground.
Light Gathering Mode
To turn the Daylight Indicator press the power button located on the face of the device.
When the power is applied, the four LEDs will illuminate sequentially from bottom to top.
Thereafter, one or more LEDs will flash every 4 seconds, indicating the amount of light
currently being received.
The Daylight Indicator measures the actual light intensity every 20 seconds, then
displays that value every 4 seconds until the next measurement is made.
Please Note
While the Daylight Indicator is gathering data, pressing the power button will turn off the unit (the four LEDs
will illuminate sequentially from top to bottom), and the measurement process will be cancelled. Pressing the
button again will start a new 24 hour measurement period.