Group 21: David Slifer Charles Wu Benjamin Humphrey Power Line Tester Group 21: David Slifer Charles Wu Benjamin Humphrey

Background Engineering World Health works in many countries helping improve the quality of life by improving medical care. Repair of medical devices Training in usage of medical devices Most of the goals of EWH are accomplished through a summer program for undergraduates.

Background “The students found that modern equipment that is often taken for granted in U.S. hospitals is in short supply in developing-world hospitals, which struggle simply to operate with uninterrupted electricity.”

Problem Statement Design a power line tester for use in hospitals in the developing world that can determine the voltage present, is the power fluctuating and third, is the outlet wired correctly

Developing Countries Reached By EWH and more…

Electrical Standards and Plug Types Each country has its own electrical standard and outlet configuration and similarities are rare. El Salvador: A, C, G, I, J, L (115V, 60Hz) Nicaragua: A (120V, 60Hz) Philippines: A, C (220V, 60Hz) Tanzania: D,G (230V, 50Hz) Ghana: D,G (230V, 50Hz) Honduras: A (110V, 60Hz) Sudan: C,D (230V, 60Hz) Haïti: A (110V, 60Hz) Sierra Leone: D,G (230V, 50Hz) Liberia: A (120V, 60Hz)

Performance Criteria Cost per unit: less than $5 Dimensions: 3 x 3 x 3” box Operable temperature: 20°C to 40°C Maintenance free Humidity

Circuit Design-Current Analysis Power tester needs to tell user 3 things: Voltage Present Is the Power Fluctuating? Is the Outlet Wired Correctly

Current Volt Testers Cost: $3.99 to $100+ Types Digital display Light Diode Light Sensitive Diode

Power Fluctuation P=Vi Do we need to know the actually power? Power fluctuation is typically cause by poor grounding and improper wiring, a short circuit and even lightning. Will testing for common problems be sufficient?

Outlet Wiring Open Ground Reversed Polarity Open Hot Open Neutral Hot Ground Wiring Reversed Hot on Neutral With Hot Open Cost: $4.99

Considerations How does each device work? How Can we combined devices? Pricing? Commercial power line tester costs >$5 All in one or separate devices? Lowest Cost with Maximum Quality How does each device work? Talk about the need to understand how the current devices work. Tell them that we have taken apart the device in the picture which test for proper wiring of device. Also we have taken apart a multimeter and are trying to understand both. How Can we combined devices? Is it possible to combind devices, Pricing? -The price to acquire the devise that do all three of our needed functions are well over $5. How can we reduce cost? -Will combining device make it cheaper or more expensive. Combing devices will reduce needed material but will it increase the completely of the circuit; thereby increasing cost? -Whatever the case may be we need to strive to keep cost low and quality high.

Goals Understand circuitry for each function Design Device Determine Pricing and redesign until price is less than $5 Patent Search Build and Test the Device? Mass Production and Distribution to Developing World Just highlight each point and add whatever you can.

Questions???