Ripple and Noise Tests
Voltages at the power supply outputs must be as “clean” as possible, with no noise or oscillation (also known as “ripple”). The maximum ripple and noise levels allowed are 120 mV for +12 V and -12 V outputs, and 50 mV for +5 V, +3.3 V and +5VSB outputs. All values are peak-to-peak figures. We consider a power supply as being top-notch if it can produce half or less of the maximum allowed ripple and noise levels.
The High Power Direct12 BR 850 W provided very low ripple and noise levels, as you can see in the table below.
|Input||Test 1||Test 2||Test 3||Test 4||Test 5|
|+12VA||9.6 mV||12.8 mV||13.8 mV||17.6 mV||20.2 mV|
|+12VB||10.8 mV||14.4 mV||18.2 mV||24.8 mV||29.6 mV|
|+5 V||9.4 mV||10.4 mV||7.2 mV||6.6 mV||8.6 mV|
|+3.3 V||9.6 mV||10.4 mV||10.8 mV||11.6 mV||14.0 mV|
|+5VSB||6.6 mV||13.4 mV||11.4 mV||15.4 mV||11.4 mV|
|-12 V||46.2 mV||44.4 mV||45.2 mV||47.2 mV||54.2 mV|
Below you can see the waveforms of the outputs during test five.
Let’s see if we can pull more than 850 W from this unit.