May06-06

Traffic Signs Outlined by Solar-Powered LEDs

Team Members

Alexander Beecher

Jason Chose

James Kopaska

Matthew Treska

Definitions

DOT - Department of Transportation

PV – Photo Voltaic (refers to solar panels)

NiMH – Nickel Metal Hydride (type of battery)

Pb-SN – Lead-Tin (type of battery)

NiCd – Nickel Cadmium (type of battery)

NEMA – National Electric Manufacturers Association

(provides a forum for electrical equipment

standardization)

Project Description

Project Description-Purpose of the signs are to raise driver awareness in potentially hazardous traffic areas

-Signs are self-sustainable, meaning they operate with minimal operator maintenance 24/7

-The stop sign is continually operating, dimming in low light in order to allow for maximum battery efficiency and limiting distractions to drivers

-The school crossing sign operates only during times of activity, determined by the user

-The chevron sign only operates in low light conditions

Project Description-LEDs will not effect shape of the sign, thus eliminating confusion to drivers

-Signs are constructed to handle various weather conditions

-Signs have anti-vandalism features, such as locks over battery and circuit casings

-An Excel spreadsheet gives criteria to the user so signs can be constructed for any locale within the continental U.S.

-Signs follow federal traffic regulations, including LED flashing no more than 60 times/min and no less than 50 times/min

Technical Specifications-System operates from a 12V NiMH battery

-Signs utilize either 55.5 Candela or 102.4 Candela LEDs

-System charges from a 14.2V solar panel

-Software interface based on Microsoft Excel

Component DescriptionPV CHARGE CONTROLLER

-Prevents over current and over voltage damage to PV panel, battery, and circuit

-Handles battery charging and power distribution to circuitry

Component DescriptionLED CLUSTER

-LED selection based on operational requirements

-55.5 Cd cluster used on night use only signs

-102.4 Cd cluster used on 24 hour operation signs

-Color specific for each sign

Component DescriptionFLASHER DIMMER MODULE

-Ensures flashing rate between 50 and 60 times per minute

-Integrated photoresistor allows automatic dimming of LEDs to match ambient light levels

Component DescriptionFLASHER MODULE

-Used on chevron sign in lieu of flasher/dimmer module

-Maintains flashing rate between 50 and 60 times/min

Component DescriptionTIMER MODULE

-Used on school crosswalk sign

-Allows user defined hours of operation

Component DescriptionPHOTOVOLTAIC PANEL

-Utilized on all signs

-Operates at 14.2V to provide sufficient energy for 12V system

Component DescriptionNiMH BATTERY

-Operates at 12V and 1.5A

-Suitable for use throughout continental U.S.

Stop Sign Specifications

-Continuous operation 24 hours a day, 7 days a week

-8 LED load @ 1120mA

-Automatically dims with changing ambient light

Stop Sign Specifications

School Crossing Specifications

-Operates 6 hours a day, 5 days a week

-5 LED load @ 700mA

-User programmable for varying school schedules

School Crossing Specifications

Chevron Specifications

-Operates in low or no light conditions, 7 days a week

-4 LED load @ 360mA

-LEDs located on 4 corners

Chevron Specifications

Circuit DemandsStop Sign

8 LED load @ 1120mA

Drive circuitry to operate flasher/dimmer @ 3.17mA

Charge controller operating current @ 30mA

TOTAL: 1153.17mA

Circuit DemandsSchool Crossing Sign

5 LED load @ 700mA

Drive circuitry to operate flasher/dimmer @ 3.17mA

Charge controller operating current @ 30mA

Timer module operating current @ 350mA

TOTAL: 1083.17mA

Circuit Demands

Chevron Sign

4 LED load @ 360mA

Drive circuitry to operate flasher module @ 3.17mA

Charge controller operating current @ 30mA

TOTAL: 393.17mA

Planned Construction

Planned ConstructionCONSTRUCTION COMPONENTS

-Telespar tubular post

-(8) BA15 LED sockets

-18 AWG wire for circuitry

-1/2” PVC conduit for wire raceway

-1/2” PVC TB junction

-Screws and other fastening tools

-36” DOT stop sign

-12 AWG wire for PV panel

-NEMA 3R enclosure

-1/2” PVC conduit straps for post mounting

-NEMA 3R junction box for back of sign

-Silicone calking

Software-Based on Microsoft Excel

-User defines the type of sign desired, geographic location of the sign, estimated hours of day usage, estimated hours of night usage, and desired number of days sign can operate without sunlight

-Calculations based on information gathered from the National Renewable Energy Laboratory

Software

Screen shot for use in Birmingham, AL

Questions??