Automatic Light Control Device

Team leader: Brad Lowe

Team members: Marshalia Green

John Thompson

Lutrisha Johnson

Faculty Advisor: Dr. Robert Reese

Team ResponsibilitiesResearch Documentation Website Micro-

controllerComponent Interfacing

Power

Supply

Marshalia Green

X X X X

Lutrisha Johnson

X X X X

Brad Lowe X X X X

John Thompson

X X X X

Abstract With the current electricity shortage, energy

conservation has become a heavy consideration. Although it makes up 17% of all electricity consumed nationally, lighting is often overlooked as a potential source of conserving energy. The automatic light control device will use photoelectric beams to detect and keep track of the occupants of a room, keeping the lights on until the last person leaves. This system could potentially reduce light usage of a room by as much as 55%.

Energy Consumption Comparisons

Comparsion of Manual Control & Sensor Control

12

23

6555

22 20

49

87 90

73 6962

0

20

40

60

80

100

0 5 10 15 20 25 30

Time of Day (hr)

Per

cen

tag

e o

f M

axim

um

Lig

hti

ng

E

ner

gy

(%)

Sensor Control

Manual Control

Money Saving Potential

• For a room with 64 20-W fluorescent bulbs, 1.28kW of power is consumed hourly.

• Studies by the Department of Energy suggest that interior lights are needlessly on for an average of 6 hours per day.

• Using the ALCD would produce a yearly savings of $140 (at $0.06 per kWh).

Disadvantages of Current Light Control Systems

• Motion and audio sensors are susceptible to activation due to false signals, and they may turn off lights if occupant stays still or remains silent.

• False activation causes the lights to needlessly cycle, which consumes more power than if they were to stay on continuously.

Design Diagram

Light

Control Unit01

Sensor

MotionSensor

Design Requirements• Power consumption:

– System will operate at 120V 60 Hz AC

– Control unit will consume a negligible amount of power (< 1.5W).

•Size

–Control unit must fit in a standard light switch socket (4.5” x 3.5” x 1.5”)

Design Requirements• Installation

– Comparable to installing a light switch (can be done by anyone with basic knowledge of electrical wiring)

• Life expectancy– Minimum life expectancy of 10 years

Design Requirements• Expandability/Adaptability to Environment

– Adaptable to incandescent or fluorescent lights via a toggle switch

– Able to manage up to 3 doorways– Optional light sensor can prevent switch

operation if light level is high enough from outside sources, such as a window

System Components

•Photoelectric Beam Sensors

•Motion Detector

•PIC Microcontroller

Test Specifications

Requirements SPICE/

Electronic Workbench

MPLAB Performance Testing

Power consumption X X

Adaptability X X

Microcontroller X X

Photosensors X

Motion Sensor X

Voltage Transformer X

AC/DC Converter X

Relay X

Schematic of Power Supply

Simulation Results of Power Supply

Schematic of Voltage Regulator

The End