Senior Design II, Mid-semester Presentation

October 5, 2010

Team MembersRead Caver•Hardware Design•Microcontrollers•Wireless Communication•Technical Documentation

Steven Price•Software Development•LCD Interfacing•Energy Metering•Hardware Implementation

James Evans•Software Design•Hardware Implementation•LCD Interfacing•Website Maintenance

Albert Shannon•Hardware Implementation•Energy Metering•Microcontrollers•Technical Documentation

Overview Introduction

Problems StatementSolution

ConstraintsTechnicalPractical

Design I Prototypes PCBs Enclosure Packaging Product Testing Plan

Introduction

SmartStat is a wireless thermostat with energy computation abilities

Used in both residential and commercial settings

Sets temperature for heat/AC to run, provides power monitoring capabilities

Thermostat module communicates wirelessly with 2 power consumption modules

NASA Sponsorship

Team SmartStat is sponsored by NASA.The team investigated the application of

wireless technologies for sensor communication.

Specifically, the IEEE 802.15.4 Standard for wireless communication was implemented.○ Emphasis on low power, low speed wireless

communications.

Problem

Currently, there is no practical way to monitor the power consumption of specific high powered systems such as AC/heating units

Solution Use low power

wireless technologySynapse Wireless IEEE 802.15.4

Monitor energy consumption with wireless nodes

Send power consumption information to control unit (thermostat)

Solution

Technical Design Constraints

Constraint Description

Temperature Reading Range and Accuracy

SmartStat must be able to read temperatures in the range of 50°F to 100°F, with an accuracy of 98% in the comfort range of 65°F to 75°F

Energy Reading Range and Accuracy

The energy monitoring modules must measure a voltage of 240Vac, maximum current of 60A, with an accuracy of 98%.

Supply Voltage The control unit must use 24Vac for supply voltage. Energy monitoring modules must use 120Vac for supply voltage.

Wireless Communication

SmartStat must communicate wirelessly using the IEEE 802.15.4 standard.

Transmission Distance

The wireless modules must have a range equal to or greater than 500ft (unobstructed line-of-sight).

Practical Constraints

SmartStat must be compatible with the different types of HVAC systems.

[1] Conventional

[2] Water and ground source heat exchangers

[3] Air source heat exchanger

Health and Safety

The control module must not allow the user to come into contact with hazardous voltages; energy monitoring modules must be sealed.

[5]

[4]

Design I Prototypes: Thermostat – Main Unit

Design I Prototypes: Energy Monitoring Modules

Main Unit Schematic

LCD screen

Synapse Module

Pic24 uP

HVAC Controls

Energy Module Schematic

Voltage Converter

Synapse Module

Energy Monitor

PCBs

Energy Monitoring PCB Thermostat PCB

Final PCBs

Energy Monitoring Node Thermostat

Enclosure

Hammond Manufacturing p/n: 1591XXCGY6” x 3.2” x 1.8”

[6]

Enclosure continued

Versa Laser CutterMicrosoft Visio used to create desired cuts

Enclosure continued

Test Cut on a sheet of paper Enclosure lid ready for laser cutting

Enclosure continued

Back of lid Front of lid after surface conditioning

Packaging Product

LCD and Button Mounting

Packaging Product continued PCB fit and Switch Mounting

Packaging Product continued Main Unit Fully Packaged

Packaging Product continued

Packaging Product continued

Ideal packaging for energy monitoring modules would be epoxy pottingExtremely rigid, weatherproof, and protectivePermanent enclosure, inaccessible after curing

○ Would be potted if released as consumer product, but deemed unnecessary for Senior Design

Testing Plans Main unit

Basic thermostat controlsSynapse wireless module communication

○ Energy data ○ Number of wireless nodes connected

Energy Monitoring ModulesEnergy metering accuracySynapse wireless communication

Synapse Wireless Modules Power Supplies

References[1] “Why Choose Us,” Broward Factor Service. [Online] Available: http://www.browardfactory.com/why-choose-us.htm [Accessed:

Feb. 22, 2010].

[2] “You Can Save 80% per month on Your Electric Bill,” Energy Trio. [Online] Available: http://energytrio.com/energytrio.html [Accessed: Feb. 22, 2010].

[3] “Air Handlers,” Amana. [Online] Available: http://www.amana-hac.com/Home/Products/AirHandlers/tabid/292/Default.aspx [Accessed: Feb. 22, 2010].

[4] “Danger High Voltage,” Speedysigns. [Online] Available: http://www.speedysigns.com/images/osha/large/DANGER50.gif[Accessed: Feb. 22, 2010].

[5] “Sign High Voltage clip art,” Clker.com. [Online] Available: http://www.clker.com/clipart-9328.html [Accessed: Feb. 22, 2010].

[6] “1591XXCGY”, Mouser.com. [Online] Available: http://www.mouser.com/Search/include/LargeProductImage.aspx?path=hammond/lrg/1591xxcgyb.jpg [Accessed: Oct. 2, 2010].

Questions?