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Load Regulation, Hold-Up Time & Inrush Current
To learn more about our PSU tests and methodology, please check out How We Test Power Supply Units.
Primary Rails And 5VSB Load Regulation
Load Regulation testing is detailed here.
Hold-Up Time
Our hold-up time tests are described in detail here.
The hold-up time we measured is pretty long, and the power-good signal is accurate.
Inrush Current
For details on our inrush current testing, please click here.
The inrush current is very low. That large NTC thermistor does an excellent job.
Load Regulation And Efficiency Measurements
The first set of tests reveals the stability of the voltage rails and the MasterWatt Maker 1200 MIJ's efficiency. The applied load equals (approximately) 10 to 110 percent of the PSU's maximum load in increments of 10 percentage points.
We conducted two additional tests. During the first, we stressed the two minor rails (5V and 3.3V) with a high load, while the load at +12V was only 0.1A. This test reveals whether a PSU supports Intel's C6/C7 power states or not. In the second test, we determined the maximum load the +12V rail could handle with minimal load on the minor rails.
| Test # | 12V | 5V | 3.3V | 5VSB | DC/AC (Watts) | Efficiency | Fan Speed | Temps (In/Out) | PF/AC Volts |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 8.174A | 1.954A | 1.972A | 0.981A | 119.773 | 91.028% | 0 RPM | 45.19°C | 0.701 |
| 12.017V | 5.104V | 3.343V | 5.078V | 131.578 | 41.14°C | 115.11V | |||
| 2 | 17.383A | 2.929A | 2.963A | 1.180A | 239.611 | 92.922% | 0 RPM | 46.02°C | 0.977 |
| 12.011V | 5.104V | 3.336V | 5.076V | 257.863 | 41.85°C | 115.09V | |||
| 3 | 26.973A | 3.427A | 3.479A | 1.379A | 359.871 | 93.693% | 0 RPM | 46.52°C | 0.980 |
| 12.005V | 5.103V | 3.329V | 5.070V | 384.095 | 42.46°C | 115.08V | |||
| 4 | 36.546A | 3.917A | 3.971A | 1.575A | 479.634 | 93.635% | 0 RPM | 47.50°C | 0.984 |
| 11.998V | 5.102V | 3.322V | 5.066V | 512.238 | 43.52°C | 115.07V | |||
| 5 | 45.794A | 4.902A | 4.975A | 1.776A | 599.608 | 93.142% | 640 RPM | 42.33°C | 0.988 |
| 11.991V | 5.102V | 3.314V | 5.065V | 643.757 | 45.13°C | 115.06V | |||
| 6 | 55.047A | 5.879A | 5.983A | 1.974A | 719.505 | 92.648% | 850 RPM | 42.79°C | 0.991 |
| 11.985V | 5.101V | 3.307V | 5.062V | 776.603 | 45.20°C | 115.06V | |||
| 7 | 64.308A | 6.864A | 7.001A | 2.169A | 839.352 | 92.057% | 975 RPM | 43.52°C | 0.993 |
| 11.978V | 5.100V | 3.298V | 5.060V | 911.777 | 45.75°C | 115.08V | |||
| 8 | 73.579A | 7.849A | 8.020A | 2.370A | 959.301 | 91.243% | 1140 RPM | 44.38°C | 0.994 |
| 11.972V | 5.100V | 3.291V | 5.059V | 1051.365 | 46.39°C | 115.06V | |||
| 9 | 83.296A | 8.335A | 8.553A | 2.369A | 1079.306 | 90.355% | 1320 RPM | 45.62°C | 0.996 |
| 11.966V | 5.099V | 3.285V | 5.061V | 1194.516 | 47.60°C | 115.06V | |||
| 10 | 92.564A | 8.826A | 9.063A | 3.481A | 1199.151 | 89.243% | 1500 RPM | 46.99°C | 0.996 |
| 11.959V | 5.099V | 3.277V | 5.020V | 1343.695 | 48.70°C | 115.07V | |||
| 11 | 102.655A | 8.826A | 9.078A | 3.484A | 1319.120 | 88.076% | 1500 RPM | 47.32°C | 0.997 |
| 11.952V | 5.099V | 3.271V | 5.020V | 1497.699 | 49.53°C | 115.07V | |||
| CL1 | 0.099A | 16.026A | 16.006A | 0.003A | 135.999 | 83.196% | 1015 RPM | 45.78°C | 0.693 |
| 12.021V | 5.096V | 3.319V | 5.200V | 163.469 | 47.80°C | 115.13V | |||
| CL2 | 99.928A | 1.003A | 1.003A | 1.002A | 1208.249 | 89.251% | 1500 RPM | 45.79°C | 0.996 |
| 11.956V | 5.104V | 3.295V | 5.074V | 1353.760 | 47.75°C | 115.07V |
Load regulation is quite good at +12V, next to perfect at +5V, and satisfactory at 5VSB. The 3.3V rail performs the worst, although it's still close to 2%. Then again, we aren't talking about your average power supply. This is an incredibly expensive one, so we're not going to be satisfied with anything short of exceptional.
The MasterWatt Maker 1200 MIJ's efficiency is very high; it has no problem delivering full power under high ambient temperatures. Moreover, the fan spins fairly slowly, keeping noise output low as well.
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