Protection Features
Desktop power supply units (PSUs) include several protection features to safeguard both the PSU itself and the connected PC components (motherboard, CPU, GPU, drives, etc.). These protections prevent damage from electrical faults, overloads, or abnormal conditions.
| OCP (Normal @ 31.5°C) | 12V: 114.60A (137.58%), 11.989V 5V: 29.1A (145.50%), 5.003V 3.3V: 31A (155.00%), 3.322V 5VSB: 4A (133.33%), 5.024V |
| OCP (Hot @ 44.1°C) | 12V: 97.00A (116.45%), 12.015V 5V: 27.1A (135.50%), 5.034V 3.3V: 29A (145.00%), 3.335V 5VSB: 4A (133.33%), 5.031V |
| OPP (Normal @ 31.0°C) | 1388.64W (138.86%) |
| OPP (Hot @ 45.1°C) | 1170.15W (117.01%) |
| OTP | ✓ (135°C @ Heat Sink) |
| SCP | 12V to Earth: ✓ 5V to Earth: ✓ 3.3V to Earth: ✓ 5VSB to Earth: ✓ -12V to Earth: ✓ |
| PWR_OK | Proper Operation |
| UVP (Full Load @ 90V) | ✓ |
| UVP (No Damage @ 80V) | ✓ |
| Conducted Emissions EN55032 & CISPR 32 | ✓ |
| NLO | ✓ |
| Fan Failure Protection | ✗ |
| SIP | Surge: MOV Inrush: NTC & Bypass Relay |
There is a significant difference between the 12V rail’s OCP triggering points under normal and hot conditions, which is the proper (and only) way to protect the PSU effectively. There is also a significant difference in the minor rail’s OCP triggering points under the same conditions, but I disagree with the increased amperage on the 3.3V rail. Lastly, the over power protection is set correctly.
The remaining essential protection features are present and functioning well, but this platform doesn’t include fan-failure protection, which is unfortunately the case for most PSUs.
EMC Pre-Compliance at a Glance
Every electronic device, including PSUs, can be an EMI source, and the amount of EMI it emits can affect the proper operation of nearby devices. EMI can, in some extreme cases, even render them unusable. Some standards have been established to minimize electromagnetic interference (EMI) noise. The corresponding standards for IT (Information Technology) products are CISPR 32 and its derivative, EN 55032, which applies to products sold in the EU. In the EU, every product bearing the “CE” marking must comply with the EN 55032 standard. CISPR 32 and EN 55032 standards categorize devices into two classes: A and B. Class B equipment is intended for domestic environments. Hence, its permitted EMI emissions are significantly lower than those of A-class devices.
Our equipment for EMI readings:
- TBMR-110M EMI-Analyzer DC-110 MHz
- Tekbox TBLC08 LISN
- Tekbox TBFL1 transient limiter
- Tekbox software
| CISPR 32 / EN55032 Limits | ||
| CISRP 32 / EN 55032 Class A Conducted EMI Limit | ||
| Frequency of Emission (MHz) | Conducted Limit (dBuV) | |
| Quasi-peak | Average | |
| 0.15 – 0.50 | 79 | 66 |
| 0.50 – 30.0 | 73 | 60 |
| CISPR 32 / EN 55032 Class B Conducted EMI Limit | ||
| Frequency of Emission (MHz) | Conducted Limit (dBuV) | |
| Quasi-peak | Average | |
| 0.15 – 0.50 | 66 – 56 | 56 – 46 |
| 0.50 – 5.00 | 56 | 46 |
| 5.00 – 30.00 | 60 | 50 |
| CISRP 32 / EN 55032 Class A 10-Meter Radiated EMI Limit | ||
| Frequency of Emission (MHz) | Field Strength Limit (dBuV/m) | |
| 30 – 88 | 39 | |
| 88 – 216 | 43.5 | |
| 216 – 960 | 46.5 | |
| > 960 | 49.5 | |
| CISRP 32 / EN 55032 Class B 3-Meter Radiated EMI Limit | ||
| Frequency of Emission (MHz) | Field Strength Limit (dBuV/m) | |
| 30 – 88 | 40 | |
| 88 – 216 | 43.5 | |
| 216 – 960 | 46.0 | |
| > 960 | 54.0 | |
Please note that the ATX spec allows a 4 dB margin for conducted and radiated emissions. This means that if a PSU exceeds the limits but stays within the 4 dB margin, it meets the corresponding ATX spec requirement (8.1 Emissions).
EMI Results
The PSU’s EMI emissions are under control.
The Cybenetics report indicates that this power supply is compliant with ATX 3.1; however, the transient testing results show issues on the 3.3 V rail.
Could you clarify how ATX 3.1 pass/fail determinations are defined in your methodology? Specifically, how are transient deviations on secondary rails, such as the 3.3 V rail, evaluated when concluding overall ATX 3.1 compliance?
Reference:
Cybenetics ATX 3.1 PASS Report
https://www.cybenetics.com/evaluations/psus/2971/
Which transient response results are you referring to? The transient response tests with normal loads, which I do, and without capacitors? These are my tests; they are not included in any ATX spec. I have been conducting these for many years now, and they are there to compare all PSUs with load on all rails directly.
The ATX v3.1 uses an entirely different transient response load scheme, which Cybenetics adopts, to check against this standard.
This standard is open, so you can study it and look at what it says about transient report testing.
based on your experience did unicon caps was better than toshin kogyo or similar with nippon chemicon, rubycon or nichicon ?
I don’t think they are better than the well-known caps, especially the last three brands you mention.
so it’s basically same tier as TK ?
I don’t have a clue unless I check enough capacitors from Unicon and TK
Interestingly, SAMA P uses a different RSY platform and shows excellent results.
Hi, Aris, do you have any idea why BeQuiet lists Cybenetics Gold efficiency and Noise A+ in its marketing materials, when all Pure Power 13 M PSUs achieved Platinum and A++?
Did they change anything after your tests or why?
They can always downgrade the badges, but never upgrade them.
…they certainly can, but what’s the point, from a marketing point of view,
…probably none.
Maybe they’re not sure about the manufacturing tolerances, who knows 👀