External Desktop and Wall Plug in Power supply / AC Adapter Output Cable Regulation Calculator

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When using a non-standard output cable with a power supply, it is useful to be able to understand the expected voltage of the new required cable for a custom application. By entering the wire gauge, cable length, output voltage and output current, the expected output regulation effect may be determined.

Since the output voltage regulation window is typically +/-5%, the window dimension may be thought of as a total of 10%. If we allow half of the 10% window for output cord voltage regulation drop, then the other half of the window can be allocated for other forms of output voltage variation such as AC line regulation, temperature variance, and component variance.

The output regulation shown has 3 background colors possibly displayed after the calculation:

Green:Output Cord Regulation is less than 4%
Yellow:Output Cord regulation is between 4% and 5%
Light Red:Output Cord Regulation is greater than 5%

If output cord regulation is greater than 5%, then the +/-5% overall regulation requirement for the power supply may be impractical, and a wider specification, such as +/-7 or perhaps +5%, -10% may be needed.


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