Engineering Projects/Power projects/Howard Community College/Spring2012/p3550K

Electronic Sections Expected

Problem Statement

The main purpose is to make LAB power supplies like other power supply projects.

The specific goals of this project are:

1. Figuring out how this power supply works

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2. Converting its outputs in order to become usable in LAB as a power supply

Team Members

Keyvan

Summary

Tried to add binding posts to a variety of power supplies, but none worked as well as the PC power supply.

Poster

Put a graphic in wikimedia, include the graphic here or link to it here. The graphic should be suitable for creating a traditional project poster.

Story

Checked power supply of old HP plotter, power supply of laser printer, and some other random power supplies. Could not take them apart and get them to work ... when disconnecting them from the original equipment something was lost that disables them. I tried putting loads on the what appeared to be the output power lines, but they still did not work. They are all switching power supplies which are delicate. Some were in the rain outside for a while.

Decision List

The only decision made was to give up on everything but pc power supplies.

Material List

Need the following tools:

wire stripper

multimeter

soldering iron and solder

drill gun

For each power supply need:

5 binding posts

1 power cord

10 ohm power resistor

LED

360 ohm resistor to protect LED

quarter roll of electricians tape

switch

Time

7 hours

Tutorials

Tutorials were created in previous projects, none new here.

Next Steps

There are about thirty pc power supplies that can be converted in the Lab as of 5/10/12. The next step is to create an assembly line with the following stations:

1. Test ... see if fan spins, if it spins it will work. If fan does not spin, strip green, red and two black wires. Hook green to black, then test voltage between red and the other black. If there is 5 volts, it will work.

2. Drill holes

3. Cut and strip off all the wires, leave room to twist them all together and then stuff the wires back into the power supply and put the lids on.

4. Solder the same colored wires together.

5. Insert binding posts and solder wire to binding posts. Solder one wire of each color to a binding post.

6. Put switch in the green wire, put led and 360 ohm in series between the gray and an unused black wire.

7. Hook power resistor up to discharge the capacitors.

May want to rotate the drilling the holes. This can get tiring. Need to invest in some sharp bits and using drilling oil with the drill press.