Topower PowerBird 900 W Power Supply Review
Overload Tests
Contents
Before overloading power supplies we always test first if the over current protection (OCP) circuit is active and at what level it is configured.
As mentioned, we discovered that OCP was set at 31 A as we couldn’t pull more than that from +12V2.
Since we were already pulling the maximum we could using our equipment (33 A from its +12V1 input and 30.5 A from its +12V2 input), the only option for us to overload this power supply was to increase current at +5 V and +3.3 V.
The idea behind of overload tests is to see if the power supply will burn/explode and see if the protections from the power supply are working correctly. This power supply didn’t burn and when we tried to pull far more than it could deliver it would shut down, so this unit passed on this test.
| Input | Maximum |
| +12V1 | 33 A (396 W) |
| +12V2 | 30.5 A (366 W) |
| +5V | 25 A (125 W) |
| +3.3 V | 16 A (52.8 W) |
| +5VSB | 3.5 A (17.5 W) |
| -12 V | 0.5 A (6 W) |
| Total | 958.3 W |
| % Max Load | 106.5% |
| Room Temp. | 49.8° C |
| PSU Temp. | 53.0° C |
| AC Power (1) | 1,162 W |
| Efficiency (1) | 82.5% |
| AC Power (2) | 1,203 W |
| Efficiency (2) | 79.7% |
| AC Voltage | 100.7 V |
| Power Factor | 0.998 |
With PowerBird 900 W delivering 950 W efficiency dropped below the 80% mark (consider the results marked as "2", as they are the correct ones, measured with our precision power meter).