1. Department of Electrical and Computer Engineering CDR Presentation Thursday February 28, 2013 Reviewed by: Prof. Bardin & Prof. Gao Paulo Leal, Kevin Okiah, Chris Finn & Tim Mirabito

2. 2 Department of Electrical and Computer Engineering Outline  MDR Recap  CDR Goals/Progress  Design Choices  FPR Goals  Demos  Cost Breakdown  Questions?

3. 3 Department of Electrical and Computer Engineering Project Recap  Project Goal Give people a means to monitor and control the electrical devices within their households.  Motivation Energy conservation has a significant social & economic impact. It is hard to conserve energy because Limited quantitative data Limited social awareness Limited residential control

4. 4 Department of Electrical and Computer Engineering MDR Recap: Block Diagram

5. 5 Department of Electrical and Computer Engineering MDR Recap: Communication Flow

6. 6 Department of Electrical and Computer Engineering Tim’s MDR Review  At MDR I had reverse engineered the critical components of the P4400 Kill-a-Watt device.  From this process, circuit schematics for each subsystem of the device were generated.  In addition, a proprietary design for a transformerless power supply was created, simulated and laid out on a PCB. The specifications of were designed to match the power requirements for our components.

7. 7 Department of Electrical and Computer Engineering Tim’s Proposed CDR Goals  Prototype modified “Tweet-a-Watt” for real-time data  Complete proprietary design of watt meter subsystems  Integrate relay and XBee layouts into proprietary design  Complete schematic and PCB layouts for a fully functioning system

8. 8 Department of Electrical and Computer Engineering Initial Power Supply Design Initial PCB layout for the transformer less power supply design schematic with a 15V and 50mA output.

9. 9 Department of Electrical and Computer Engineering Design Revision: Power Supply  Initial design for a transformerless power supply presented efficiency & fail safe challenges. Conversion Efficiency of ~10%  Opted instead for a commercial power supply in a fail safe configuration. CUI Series VSK-S1 Model 5U

10. 10 Department of Electrical and Computer Engineering Design Revision: Power Supply

11. 11 Department of Electrical and Computer Engineering Design Choice: Relay Circuit The simulation results for the XBEE trigger showing relay control

12. 12 Department of Electrical and Computer Engineering Design Choice: Current & Voltage Sense Utilization of the INA128P instrumentation amplifier from Texas Instruments was chosen due to the design being specifically applicable to our objective and high CMRR of 130dB.

13. 13 Department of Electrical and Computer Engineering Current & Voltage Sense Subsystem Circuit schematic and simulation output from the implemented design show the voltage values corresponding to current and voltage readings being sent to the XBEE.

14. 14 Department of Electrical and Computer Engineering Paulo’s Goals/Progress  Build Tweet a Watt  Networking Circuit Setup XBee Network Transmit data wirelessly from model A to B Control Switching Mechanism  Relay Circuit Design & Test

15. 15 Department of Electrical and Computer Engineering Overview - Design Choice: Tweet a Watt

16. 16 Department of Electrical and Computer Engineering Overview - Design Choice: XBee Wireless Radios  XBee Series 1 Indoor Range: 100ft. RF Data Rate: 250Kbps Frequency: 2.4 GHz AES encryption Analog to Digital converter

17. 17 Department of Electrical and Computer Engineering Overview – Previous Design Choice: Relay CKT  PowerSwitch Tail for 110-120vac Provide single pole switching at 20 amps 5300vrms isolation Driving voltage as little as 3vdc @ 3ma Cost: $ 18.50

18. 18 Department of Electrical and Computer Engineering New Design – Relay Circuit  Outlet Switching Circuit Relay – 220V @ 20A NPN transistor controls coil current (80mA) R1 pulls the trigger pin to ground so if anything goes haywire the relay will remain in the safe (Off) Diode – protects power supply and nearby parts Cost: $5

19. 19 Department of Electrical and Computer Engineering Christopher’s CDR Goals/Progress  Parse XBee input  Allow connection from user interface to database Over internet via port forwarding  Relay circuit control Integrated with user interface buttons  Security SSL for apache server User account database/login system AES XBee communication encryption

20. 20 Department of Electrical and Computer Engineering Quick Review of Design Choices  Raspberry Pi 700 MHz ARM computer Runs custom Debian Linux Utilize Linux packages  LAMP Server  Python Serial communication to/from XBee Data processing Database interactions Raspberry Pi GPIO control

21. 21 Department of Electrical and Computer Engineering Security  Generated Self-Signed SSL Certificate Has to be manually trusted by browser to suppress warnings  Login system Table of user/md5(password) combos PHP sessions  XBee 128bit AES encryption

22. 22 Department of Electrical and Computer Engineering Data Flow: Outlet Data

23. 23 Department of Electrical and Computer Engineering Data Flow: Relay Control

24. 24 Department of Electrical and Computer Engineering Additional Design Notes  Physical Storage Requirements Trade off between accuracy & storage size Past Year Minute intervals => 4.2MB per outlet per year >1 Year Fifteen Min. intervals => 280KB per outlet per year Total per outlet = 4.2MB + 4*280KB = 5.3MB Est. Household Total (5 yr, 100 outlets) = ~0.5GB

25. 25 Department of Electrical and Computer Engineering Kevin’s MDR Recap /CDR Goals  Developed a Basic user interface prototype that is functional across all operating system Network Interface

26. 26 Department of Electrical and Computer Engineering Kevin’s MDR Recap /CDR Goals Continued  Plotting functionality FLOTAwesomeChartJS  Demonstrated plotting data by successfully querying the database  User Interaction with the system was Limited  Function to receive and send relay Signal  Develop a function to assimilate new devices to the system

27. 27 Department of Electrical and Computer Engineering PROGRESS Programing Languages  HTML5  CSS  JavaScript  PHP  JQUERY

28. 28 Department of Electrical and Computer Engineering Progress continued Main Functions Real-time data Account summary Usage History Your Energy Cost Devices

29. 29 Department of Electrical and Computer Engineering Demos!

30. 30 Department of Electrical and Computer Engineering FPR Group Goals  Chris Multi-room integration (via HomePlug) User defined storage intervals Downloadable ZIPs of table data Optimize data calculations Code revisions Clean up & optimize  Tim Professor review of preliminary PCB layout for manufacture. Implementation of scalability functions: Multiple 120V Outlets 240V Outlet Interface Increased Sampling Rate  Paulo Expand Wireless Network to multiple rooms Finalize Integration Process within blocks Design a safe and minimized final enclosure  Kevin Seamless assimilation of new devices to the PowerPi system Expand my plotting functionality to accommodate more than one device/ outlet. Improve user interaction by giving users more control over the system

31. 31 Department of Electrical and Computer Engineering Full Circuit Schematic

32. 32 Department of Electrical and Computer Engineering XBee Explorer Using the current design of the XBee Explorer as a foundation, the final implementation of the watt meter PCB will have a subsystem with pin out headers for easy upgradability.

33. 33 Department of Electrical and Computer Engineering Full Circuit PCB Layout  PCB layout done via Cadsoft’s EAGLE  Top & Bottom Layered with copper grounding.  Part outlines established via silk screening.  Board Size: 119mm x 105mm

34. 34 Department of Electrical and Computer Engineering PCB Fabrication  PCB fabrication can be done at many companies; some of the ones I’ve looked at: Custom Circuit Boards, LLC. in AZ E-Teknet, Inc. in AZ PCB Solutions LLC in NV Fineline Circuits & Technology, Inc. in CA PCB FAB EXPRESS in CA  The cost to fabricate a single board will cost $60- $100 dependent on board layering, and size.  The turn around time varies from 3 to 10 days.

35. 35 Department of Electrical and Computer Engineering Cost Breakdown QTYUOMUnit PriceDescriptionTotal 11$35.00Raspberry PI Model B$35.00 31$19.49P3 International P4400 Kill A Watt Electricity Usage Monitor$58.47 11$49.99Actiontec PWR511K01 500 Mbps HomePlug HD Power line Wall Plug Network Adapter $49.99 11$3.95Jumper Wires Premium 6“ M/F Pack of 10$3.95 11 Jumper Wires Premium 6" F/F Pack of 10$3.95 31$3.00T9A Series Relay$9.00 21$19.00XBee Series 1 XB24-AWI-001XB24-AWI-001$38.00 51$21.00Prototype PCB$105.00 51$11.01VSK-S1 Power Supply$55.05 Total$358.41

36. 36 Department of Electrical and Computer Engineering Questions