eTeknix Power Supply Testing Methodology

Anyone who has studied physics at school will know that efficiency is very simple, just the case of output energy/input energy, the same applies here. While I’m testing the voltage stability at each load, I switch the tester to wattage mode and find out the total wattage being pulled from the unit by the tester.

This is duly noted and logged in my previously mentioned magic spreadsheet. Then I consult the wise GW Instek GPM-8212 which is an inline power meter which measures the AC wattage being pulled by the PSU, the wattage is also added to the spreadsheet. The two are divided and multiplied to give me the efficiency percentage, simple- in principle anyway!

As you can also see on the power meter, on the upper-right hand corner it is set up to display the power factor. Due to the simplicity of this, there is little point writing a page about it, but this is how we measure the PF.