CHOOSING YOUR LED LIGHTING SYSTEM
The Heat-sink
The LED
A heat-sink is a passive heat exchanger
that transfers heat from an electrical
device to a coolant. For horticultural
LEDs, the heat-sink transfers heat from
the LED or string of LEDs to the air,
which acts as the coolant. Most heatsinks look like big, thick, metal combs
and are usually placed near the unit’s
cooling fan. The teeth of the comb
allow the heat produced by the electrical current to be transferred to the air.
When shopping around for a lighting
system, it is important to examine both
the heat-sink and cooling fan. Larger
heat-sinks combined with a cooling fan
are nice for indoor gardens because
the ambient temperature of an indoor
garden can run higher than normal
living quarter conditions. If the system
is not effectively cooled by its heat-sink
and fan, the unit will operate less efficiently and degrade at a faster rate.
Just as not all HID light bulbs perform
the same for horticultural purposes,
there can be a lot of variety in the
diode, or LED itself, in a lighting
system. The spectrum emitted by the
diode is crucial to the effectiveness
of the lighting system. Particular
wavelengths of light are more easily
absorbed by plants during photosynthesis and are used more frequently by
plants than other spectrums.
In fact, some wavelengths of light are
hardly used at all by plants. Lighting
systems that produce the most usable
ratio of wavelengths will be more
efficient than those that do not. This
is the main reason why LEDs are so
exciting for the indoor gardening
industry. The ability to customize
LED lighting systems means not only
more efficient lighting systems, but
also the ability to experiment with the
“The light emitted from an LED is the
result of the current passing through
the silicon in the diode.
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Maximum Yield USA | November 2015