Static electricity/Howard Community College/Fall2012/p3-502-hkm/StyrofoamCutter

In order to repair the styrofoam cutter that was in the shop, I had to replace the power supply that had previously stopped working and add a resistor to prevent the new power supply from failing. I started by sketching and labeling the power supply.

Test 1
I proceed to to replace the broken power supply with a new one that had an output of 7.5 volts and 1 amp. I also added an 8 ohm resistor. The test was unsuccessful as the resistor started to smoke as soon as the device was plugged in and was dubbed a failure.

Test 2
I swapped out the burned resistor with four 10 ohm resistors that paired in parallel that combined for a resistance of 14 ohms when put to a voltmeter. After implementing these resistors with the same power supply, I tested the Cutter again. This time, the resistors did not smoke, but the device was unable to cut the styrofoam.

Test 3
I upgraded to a new power supply with an output of 12 volts and 1 amp in hope that the increased voltage would cause the device to cut the styrofoam with the same resistor layout. I implemented the new power supply and tested the device again, but I was still unable to cut the styrofoam.

Test 4
I decided to go back to what I knew would work for a certain amount of time and removed the resistors from the design. This design was the original and still ran the risk of the power supply burning out like the original. Fortunately, the device worked and there is a video of this test at [].

After these test, the original design proved to be the most effective, but still runs the risk of the power supply failing. In order to operate, it can't be plugged in for more than 15 seconds at a time to keep the device working. One possible solution to this would be to implement a switch into the design so that it is easier to turn off and on. It is also possible that there is a resistor configuration that will work to prevent the power supply with failing.

Implementing the Switch
The switch that will be implemented is an old single-pole double-throw, and will be implemented into the wood of the styrofoam cutter. Information on single-pole double-throw switches can be found athttp://www.1728.org/project2.htm.

Before the switch was implemented, it had to be tested to make sure that it still works. In order to do this, it was connected to a 5V 1.5A power supply. After these tests were run and succeeded, the space in the wood of the cutter had to be made. The approach chosen was to drill a series of holes in the area that the switch will go and use the dremel tool to smooth out the edges. The switch can now be placed into the space and wired up so that it will function correctly.. The switch was then tested and proved to be a successful implementation, and the video of the working cutter with the switch is at http://www.youtube.com/watch?v=aHtrD9w_xA0&feature=youtu.be. After the hole was completed, the