Page 63 - Sensors and Control Systems in Manufacturing

The Role of Sensors in the 21st Century
it is related to volts and amps by the formula: volts × amps × power 25
factor = watts.

1.12.10 Watts per LED
It can be confusing when two watt numbers are used in product spec-
ifications. For the application to SMD high-powered LEDs, the 1 watt,
3 watt, and 5 watt classifications (and so on), refers to the power con-
sumption of that specific LED installed in that product. The watt num-
bers expressed as light output are a comparison to an incandescent
light bulb light output (e.g., a 60-watt light output is equal to a 60-watt
incandescent light bulb). The watt output is equipment measured.

1.12.11 Weatherproof
Weatherproof means the product can endure splashing water and
high humidity without deterioration to the LED or circuit. Weather-
proof LED products cannot be submerged into water.

1.12.12 White
White is defined by Kelvin temperature or degrees Kelvin. A Kelvin
temperature of 6000 K is white with a blue tint. 5000–5500 K is a day-
light/sunlight white. At 4200–4500 K, it is called cool white. At 2800–
3300 K, it is warm white, which is the color temperature that the
majority of incandescent light bulbs emit. The color becomes “warmer”
from 5500 K down the scale, due to the dominance of red and yellow
hues. In the opposite direction, whites will have cooler colors, with
blues and greens becoming more apparent, thus they are called cool
whites.

1.13 The Basics on LEDs
How does an LED work?
The following outlines some basic principles of an LED.

• White LEDs need 3.6 V DC and use approximately 30 milli-
amps of current; a power dissipation of 100 milliwatts (mW).
• The positive power is applied to one side of an LED semicon-
ductor through a lead often called an anode, and another lead
called a whisker.
• The other side of the semiconductor is attached to the top of
the anvil. This is the negative power lead, which is called the
cathode.
• It is the chemical makeup of the LED semiconductor that
determines the color of the light the LED produces.