Completed Project Power Supply Accessory, Shorting Box

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Joined Mar 24, 2008
Modern power supplies are great, they regulate both voltage and current. The current regulator has one problem, before you connect a device such as a LED you first have to discharge the filter caps or you will blow the component you trying to test! This device allows you to short the PS, set the current, connect the UUT, and remove short. It will even show you the drop voltage of the UUT on the PS. First, set the max voltage,that the device will likely drop. Connect the UUT remove the short and the result are displayed on the PS display. If you want to enlarge the picture just click on the image.

Shorting Box 1.jpg
This is the box. Do you really need a schematic?

Shorting Box.jpg

]Shorting Box 2.jpg
First set the voltage...​

Shorting Box 3.jpg
Short it out and set the current ( UUT is a green LED)...​

Shorting Box 4.jpg
And Walla! Its specs are on the display.​
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