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 better 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 and if the outlet is wired correctly
Social Impact Developing world hospitals are plagued with faulty outlets Power line tester will identify the faulty outlets and the problem Expensive medical equipment will only be used in working outlets, saving the equipment and possibly people’s lives.
Developing Countries Reached By EWH and more…
Performance Criteria Determine Voltage Present Is the Outlet Wired Correctly? Cost per unit: less than $5 Dimensions: 3 x 3 x 3” box Operable temperature: 20°C to 40°C Maintenance free Humidity
Current Volt Testers Cost: $1.99 to $100+ Types Digital Display Light Diode Light Sensitive Diode
Outlet Wiring Open Ground Reversed Polarity Open Hot Open Neutral Hot Ground Wiring Reversed Hot on Neutral With Hot Open Cost: $4.99
Voltage Indicator
Outlet Wiring Tester
Combination Circuit
Considerations Combining Devices Pricing? Separate solution for each country Cheaper to design for each individual electrical standard We have determined that we can combined the circuits for each function in parrellel. This will keep cost down by using keeping duplicaiton of parts down. For example we only need one outlet hookup instead of two(one for each device) In addition, separate solutions will keep cost down. Instead of having a devices with 20 lamps, we can have one with 3, or 5.
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)
Other Considerations
Validation Working Design Operable Temperature Humidity Dimensions Pricing
Pricing total # Unit Price(1000) Price Per Device Breadboard 1 1.17618 Resistors 10 0.01222 0.1222 Zener Diode 0.024 Lamps 5 0.332 1.66 LED 0.35 Casing 1.52 total 4.85238
Questions???