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Correctly testing power supplies is a complex procedure and KitGuru have configured a test bench which can deliver up to a 2,000 watt DC load.
We test ambient temperatures at 35c in our environment to greater reflect warmer internal chassis conditions.
We use combinations of the following hardware:
• SunMoon SM-268
• CSI3710A Programmable DC load (+3.3V and +5V outputs)
• CSI3711A Programmable DC load (+12V1, +12V2, +12V3, and +12V4)
• Extech Power Analyzer
• Extech MultiMaster MM570 digital multimeter
• SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa)
• Digital oscilloscope (20M S/s with 12 Bit ADC)
• Variable Autotransformer, 1.4 KVA
We test in a single +12V configuration.
|
DC Output Load Regulation
|
||||||||||
|
Combined DC Load |
+3.3V
|
+5V
|
+12V
|
+5VSB
|
-12V | |||||
|
A
|
V
|
A
|
V
|
A
|
V
|
A
|
V
|
A | V | |
|
100W
|
0.90
|
3.35
|
0.90
|
5.02
|
7.35
|
12.02
|
0.50
|
5.01
|
0.20
|
-12.02
|
|
200W
|
1.60
|
3.35
|
1.64
|
5.01
|
15.13
|
12.01
|
1.00
|
5.01
|
0.20
|
-12.01
|
|
500W
|
3.20
|
3.34
|
3.25
|
5.00
|
38.60
|
12.00
|
1.50
|
5.00
|
0.20
|
-12.01
|
| 750W |
4.03
|
3.34
|
4.16
|
4.99
|
58.53
|
11.97
|
2.00
|
5.00
|
0.30
|
-12.01
|
|
1000W
|
5.45
|
3.34
|
5.51
|
4.98
|
78.13
|
11.90
|
2.50
|
5.00
|
0.30
|
-12.00
|
The load regulation of this power supply is acceptable, although far from the best we have seen in the last two years from a variety of OEM partners.
| ENDORFY Supremo FM5 Gold 1000 W | Maximum Load |
| 1010W |
The power supply managed to deliver 1000W, but not much more, hitting 1010W before shutting down.
Next we want to try Cross Loading. This basically means loads which are not balanced. If a PC for instance needs 500W on the +12V outputs but something like 30W via the combined 3.3V and +5V outputs then the voltage regulation can fluctuate badly.
| Cross Load Testing | +3.3V | +5V | +12V | -12V | +5VSB | |||||
| A | V | A | V | A | V | A | V | A | V | |
| 885W | 2.0 | 3.34 | 2.0 | 5.01 | 72.0 | 11.92 | 0.2 | -12.00 | 0.50 | 5.00 |
| 240W | 20.0 | 3.28 | 23.0 | 4.95 | 2.0 | 12.04 | 0.2 | -12.01 | 0.50 | 5.01 |
The Endorfy Supremo delivered decent results with some noticeable fluctuation on the minor rails when hit with high amps. The +12V rail dropped to around 11.92 when hit with 72amps.
We then used an oscilloscope to measure AC ripple and noise present on the DC outputs. We set the oscilloscope time base to check for AC ripple at both high and low ends of the spectrum. ATX12V V2.2 specification for DC output ripple and noise is defined in the ATX 12V power supply design guide.
|
ATX12V Ver 2.2 Noise/Ripple Tolerance
|
|
|
Output
|
Ripple (mV p-p)
|
|
+3.3V
|
50
|
|
+5V
|
50
|
|
+12V1
|
120
|
|
+12V2
|
120
|
|
-12V
|
120
|
|
+5VSB
|
50
|
Obviously when measuring AC noise and ripple on the DC outputs, the cleaner (less recorded) means we have a better end result. We measured this AC signal amplitude to see how closely the unit complied with the ATX standard.
| AC Ripple (mV p-p) | ||||
| DC Load | +3.3V | +5V | +12V | 5VSB |
| 100W | 10 | 5 | 15 | 10 |
| 250W | 10 | 5 | 25 | 10 |
| 500W | 15 | 10 | 35 | 15 |
| 750W | 20 | 15 | 50 | 15 |
| 1000W | 20 | 15 | 60 | 20 |
Ripple noise suppression falls within safe parameters, although far short of the market leaders in this segment.
|
Efficiency (%)
|
|
|
100W
|
88.6
|
|
250W
|
90.3
|
|
500W
|
92.1
|
|
750W
|
91.3
|
|
1000W
|
89.2
|
The efficiency results are fairly decent, peaking at 92.1% at close to 50%. This drops to 89.2% efficiency at full load.
We take the issue of noise very seriously at KitGuru and this is why we have built a special home brew system as a reference point when we test noise levels of various components. Why do this? Well this means we can eliminate secondary noise pollution in the test room and concentrate on components we are testing. It also brings us slightly closer to industry standards, such as DIN 45635.
Today to test the Power Supply we have taken it into our acoustics room environment and have set our SkyTronic DSL 2 Digital Sound Level Meter (6-130dBa) one meter away from the unit. We have no other fans running so we can effectively measure just the noise from the unit itself.
As this can be a little confusing for people, here are various dBa ratings in with real world situations to help describe the various levels.
KitGuru noise guide
10dBA – Normal Breathing/Rustling Leaves
20-25dBA – Whisper
30dBA – High Quality Computer fan
40dBA – A Bubbling Brook, or a Refrigerator
50dBA – Normal Conversation
60dBA – Laughter
70dBA – Vacuum Cleaner or Hairdryer
80dBA – City Traffic or a Garbage Disposal
90dBA – Motorcycle or Lawnmower
100dBA – MP3 Player at maximum output
110dBA – Orchestra
120dBA – Front row rock concert/Jet Engine
130dBA – Threshold of Pain
140dBA – Military Jet takeoff/Gunshot (close range)
160dBA – Instant Perforation of eardrum
|
Noise (dBA)
|
|
|
100W
|
<28.0
|
|
250W
|
<28.0
|
|
500W
|
30.2
|
|
750W
|
31.3
|
| 1000W | 35.4 |
The large fan does not make much noise at all during all load situations. This is one of the key points that ENDORFY pointed out when they sent us the sample. Low noise levels at any load.
|
Temperature (c)
|
||
|
Intake
|
Exhaust
|
|
|
100W
|
37
|
41
|
|
250W
|
38
|
45
|
|
500W
|
40
|
53
|
|
750W
|
45
|
56
|
|
1000W
|
46
|
61
|
The large fan works well in maintaining quiet noise levels, however due to the low rotational speeds and the focus on acoustic performance, the unit does get a little hotter than most we have tested in the 80 Plus Gold sector, especially as we get to around 750 watt load and above – when we feel the unit would definitely benefit from increased air flow.
Additionally, we feel if the unit had more than a single heatsink it may have coped a bit better in this test. Especially with a modest rated 80 Plus gold efficiency.
|
Maximum load
|
Efficiency
|
|
1010W
|
89.0
|
Pushing the PSU above its rated limits generates an efficiency level of around 89.0%.
