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 @ 27.1°C) | 12V1: 42.60A (129.09%), 11.889V 12V2: 43.80A (132.73%), 11.773V 12V3: 63.847A (141.88%), 11.75V 12V4: 63.851A (141.89%), 11.744V 5V: 30.5A (127.08%), 4.958V 3.3V: 31.1A (124.40%), 3.195V 5VSB: 5A (166.67%), 4.933V |
| OCP (Hot @ 44.8°C) | 12V1: 42.30A (128.18%), 11.911V 12V2: 43.40A (131.52%), 11.783V 12V3: 58.65A (130.78%), 11.779V 12V4: 58.852A (130.78%), 11.771V 5V: 30.6A (127.50%), 4.95V 3.3V: 30.198A (120.79%), 3.18V 5VSB: 4.9A (163.33%), 4.932V |
| OPP (Normal @ 31.1°C) | 1547.07W (128.92%) |
| OPP (Hot @ 45.1°C) | 1442.06W (120.17%) |
| OTP | ✓ (120°C @ 12V 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 |
Evaluating the protection features on multiple 12V rail PSUs is a pain. Please let me start with that.
The 12V OCP triggering points are correctly set. I won’t complain about the slight differences between the standard and high temperature OCP triggering points for 12V1 and 12V2, since they are conservatively set. Whereas the differences at 12V3 and 12V4 OCP triggering points are significant. These rails power the 12V-2×6 sockets.
On the minor rails, the 5V rail’s triggering points are almost similar, but there is a difference at 3.3V. Typically, the 5V rail’s hot OCP threshold should be set lower than the cold one, but in either case, both are notably below 130% so I won’t mark this as a (major) con.
The over-power protection is correctly set, and the rest of the protection features are present and work well. My only complaint is that fan failure protection is not present, which should be standard on a high-end platform.
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:
- Rohde & Schwarz FPC1500 (loaded with all options)
- Tekbox TBLC08 LISN
- Tekbox TBFL1 transient limiter
- Tekbox EMCview 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.
Oh, good timing for this review ;-). Managed to order this psu, for 250€ @Alternate.
It will replace my older BQ DP 12 850W, for more future proof.