How to Compare LED Lights When Buying in Bulk With the increase in popularity of
LED lighting, many people are confused when it comes to choosing an LED
lamp.
First we should understand that the quality and price of lamps are
determined by four components: LED chip, LED driver, Heat Sink and Printed
Circuit Board (PCB).
1. LED Chip
One of the two most important
components of an LED lamp, chips come in a wide range of performance standards
and consequently the price will vary depending upon the brand of chip used by
the manufacturer. While high performance lamps use CREE or OSRAM; the price may
be a little rich for most consumers. Instead, you may want to opt for a lamp
with a chip from Bridgelux, Samsung or Epistar to name but three affordable,
quality chips.Use of a good quality chip results in beautiful color, (as gauged
by its color temperature and color rendering index - CRI), as well as high
luminous efficacy (a measure of how well a light source produces visible
light).
Chip lengths are measured in millimeters (mil) and one millimeter
equals one thousandth of an inch. Generally, the larger the chip the better the
performance. As specifications and claims by manufacturers tend to be
over-stated Rigid flex Board, it is
prudent to compare one lamp with another by determining which components are
used in the manufacture of the products in question.
Many manufactuers
use SMD LED chips in indoor lighting, such as SMD 2835 in LED tubes, and SMD
3014 in LED panel lights. These low power LEDs produce fewer lumens resulting in
a light that is easy on the human eye. Simply put, a lumen is a measurement of
the amount of light emitted per second. High power LEDs are used in industrial
lamps due to their small size and the result is a concentrated light that does
an excellent job. Many LED high bay lamps are fitted with 45x45 mil chips and
are used and packaged with a chips on board (COB) light source.
For your
information, the numbers 2835, 3014, 3528, 5050, 5630 are the names of packaging
process models. Another process with a very promising future is the previously
mentioned COB light source, where chips are mounted directly on the printed
circuit boards (PCB) as opposed to surfaced mount devices (SMD). As these light
sources have a variety of features, it's recommended you take a few minutes to
familiarize yourself with them in order to best satisfy your
requirements.
As you have seen, LED packaging is closely related to its
performance and manages a number of functions including heat dissipation, light
distribution and varying the color temperature and CRI of the chip.It is
interesting to note that a chip that produces white light has yellow phosphor
added to it to change the original blue light it initially produces to white.
2. LED Driver
The second key component is the power system,
commonly referred to as the driver. It is the limiting factor in the longevity
of the LED lamp - while there is an urban myth that alleges the life span of a
lamp is as much as 30 years; the driver might only last 1000 to 2000 hours. So
ignore manufacturer claims of 50,000 hour of LED lamp life.
A reputable
driver, such as Meanwell, can be expected to have 15,000 hours of life. However,
the cost would be 80% higher than the average driver manfactured in China. Most
manufacturers use their own driver. In these cases it is wise to ask if the
capacitor comes from a reputable maker.
Another indication of the life
is the warranty offered.
3. Heat Sink
LEDs are temperature
sensitive making the heat sink an important concern. Most products use an
aluminum alloy heat sink for its cost efficiency and while the specifications
don't really tell us much, there are three items we should look at.
A.
Thermal conductivity: die-cast 6063 aluminum is the most common material used.
The better ones have anodized coating. B. Quantity and size of fins: the more
and the bigger the better. C. Heat pipe is used in some high power LED lamps Rigid flex PCB.
4. Printed
Circuit Board
The material used and the design of a PCB is important as
it connects the chip to the heat sink. A PCB with low thermal conductivity
results in a hot lamp. Metal and ceramic core PCBs have a good heat transfer
coefficient but most manufacturers choose fiberglass to save money.
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