Programmable Power Relay Senior Design II Midterm Presentation
Team Members Jameson Mitchell Electrical Engineering PC to PIC communication GUI Design David Null Electrical Engineering TRIAC control Firmware Design Research and Documentation Schematic Design PCB Layout Rick Wolbrecht Electrical Engineering Packet Encoding GUI Design Lane Simmons Electrical Engineering Team Leader Firmware Design Website Design Research and Documentation
Overview Introduction Problem Solution Practical Constraints Technical Constraints Senior Design II Additions Test Plan Schematic Future Plans
Introduction What’s the PPR supposed to do? Control device power using schedule Allow automated control Minimize need for user input after schedule is set +
Problem Current power strips have few features No programmable timing schedule No interactive user interface No dimming capability Few methods to exercise schedule control over electronic devices. Unable to control power when away from device
Solution "Smart" power strip with enhanced features o Programmable Timing Schedule for AC-switching o PC software application Possible Target Markets Automation Security
Practical Constraints
Health and Safety Must conform to Underwriters Laboratories (UL) standards for safety o Non-conducive Casing o Fused Overcurrent Protection
Economic Must be manufactured for less than $50
Technical Constraints Real time clock must operate at all times, under all power conditions Timing schedule accuracy must include Years, Months, Days, Hours, Minutes, Seconds PC is required to operate user interface Must supply power to internals from 120VAC Switching power must operate up to 120VAC at 15A (NEMA 5-15 Standard) [1] Must support output dimming
Technical Constraints Results From Design I RTCC OperationPass Timing Schedule AccuracyPass PC OperationPass AC/DC Power SupplyPass Power OutputPass Output DimmingFail
Technical Constraints Results in Design II RTCC OperationPass Timing Schedule AccuracyPass PC OperationPass AC/DC Power SupplyPass Power OutputPass Output DimmingPass
Senior Design II Additions Independent second output Support for event repeats Support for event deletes through the PC interface Output Dimming
Test Plan PC Exception Handling Additional Power Output Event Repeats Output Dimming
Software Improvements in SD2 Fixed Text File I/O problems Error-checking in GUI interface Added Ability to View Scheduled Events
Error Checking
GUI Updates
Additional Power Output
Hardware Triac Optoisolator Firmware Sorting Algorithm
Additional Power Output Test Results
Event Repeats Old sorting algorithm ignored expired events New sorting algorithm recognizes repeat flags in expired events and skips the event to the correct RTCC comparison.
Event Repeat Example
Event Repeat Test
Output Dimming Improvements Interrupt driven Triac pulsing
Output Dimming Tests
Eagle Schematic
PCB Layout
Future Work PCB Order Parts for PCB Populate board Order an Enclosure Event Deletes in Software
Questions ?
References [1] Powercords Online, "IDC Plugs - Standards," [Online]. Availible [2] "Appliance Wiring Material, UL 758." Underwriters Laboratories. Accessed September 16, [3] “Isolé® IDP-3050 Plug Load Control.” WattStopper. &type=Commercial. Accessed August 27, &type=Commercial [4] “Bits Energy Saving Smart Strips.” Bits Limited. Accessed August 27, [5] “6-PIN Dip Random Phase Optoisolators Triac Driver Output.” Programmable Power Relay Datasheets. M.pdf. Accessed December 1, M.pdf