Protection Features
OCP (Normal @ 28.8°C) | 12V: 66.00A (122.00%), 12.151V 5V: 28.7A (143.50%), 5.009V 3.3V: 29.3A (146.50%), 3.337V 5VSB: 4.2A (140.00%), 5.036V |
OCP (Hot @ 41.8°C) | 12V: 62.60A (115.71%), 12.161V 5V: 28A (140.00%), 5.01V 3.3V: 28.7A (143.50%), 3.338V 5VSB: 4.2A (140.00%), 5.036V |
OPP (Normal @ 29.2°C) | 803.07W (123.55%) |
OPP (Hot @ 43.0°C) | 781.02W (120.16%) |
OTP | ✓ (154°C @ Heat Sink) |
SCP | 12V to Earth: ✓ 5V to Earth: ✓ 3.3V to Earth: ✓ 5VSB to Earth: ✓ -12V to Earth: ✓ |
PWR_OK | Proper Operation |
NLO | ✓ |
Fan Failure Protection | ✗ |
Conducted Emissions EN55032 & CISPR 32 | ✓ |
UVP (Full Load @ 90V) | ✓ |
UVP (No Damage @ 80V) | ✓ |
SIP | Surge: MOV Inrush: NTC & Bypass Relay |
The 12V rail’s OCP triggering points are conservatively set despite the unit’s relatively low capacity. The 5V rail’s OCP is correctly set, since there is a difference (not that high, though) between normal and high operating temperatures. There is also a difference in the OCP settings of the 3.3V rail; however, the respective triggering points are set unnecessarily high. There is no need for such high amperage at 3.3V. Nonetheless, since OCP at 3.3V is set lower at high temperatures, I won’t hold the high OCP setting on this rail as a non-award factor.
The over power protection is set correctly, and the rest of the protection features are present, but fan failure protection, which should be standard on every modern PSU platform, is not.
EMC Pre-Compliance at a Glance
Every electronics device, including PSUs, can be an EMI source, which, depending on the amount of EMI emitted, 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
There is a single peak over the respective limit here. The Quasi-peak EMI detector will likely eliminate the respective peak, and either way, there is a 4 dB margin allowed by the ATX v3.1 spec.