Before overloading power supplies we always test first if the over current protection (OCP) circuit is active and at what level it is configured. We configured current on +12V1 to 1 A and increased current on +12V2 to 33 A and the power supply didn’t shut down. This means that either the OCP circuit is disabled or is configured at a value above 33 A. We don’t like this, especially when the label says the +12V1 rail has a 25 A limit and +12V2 rail has a 20 A limit.

This unit, however, has over power protection and we saw it in action. If we tried to pull too much power from this unit it would shut down, what is great. Below you can see the maximum we could pull from this power supply without it shutting down. Noise level at both +12 V rails was around 72 mV. See how efficiency was still above 82%.