Recommend me a power brick

[LaserHosen]

Hi,

I've just bought a 80W wide range Mini-Box PicoPSU. It'll accept 12-32v input and I'm looking for a brick that's efficient and reliable without being over priced.

The Pico is gonna be powering my NAS, which is a headless Bay Trail celeron duo setup, 8GB low voltage (1.35v) RAM pair and 2 x 2.5" HDD's. The OS (FreeNAS) is running on a USB stick.

At the moment it's running on a generic 300W ATX PSU which is at least five years old.

I haven't got a watt-meter, but the Bay Trail motherboard is supposed to draw 10-15W at full load and the two drives I suspect are drawing about 1W each. It's turned on 24/7, so I reckon the vast majority of the time it's drawing less than 10W. Hence my decision to remove the inefficient 300W PSU and whack a Pico in there.

Any recommendations for a 12v/5A brick (or even lower o/p!) to get the best efficiency?

Thanks.

[Abula]

Remember that depending on the HDD... there are higher requierments during the startup, this is quote from Limetech recommendations into PSU, The Power Supply Thread.

A good PSU for unRaid has the following:
1. Single 12 volt rail. A subsequent figures refer to the 12 volt rail.
2. The minimum capacity that can power your build. Any more will just waste power. All drives will be in use during startup, shutdown, parity check, parity build, failed drive emulation, and drive rebuild, but startup requires the most power.
3. 2 amps (24 watts) per green drive and 3 amps (36 watts) per non-green drive on the 12 volt rail.
4. 5 amps (60 watts) for the motherboard on the 12 volt rail.

Disregarding the motherboard and cpu, and if you decide to follow the above recommendation, you will need at least 4amps on the 12V rail for the two hdds. I leave you the bricks that have worked well for me over the years, i believe they are energy level 5 and they feel solid and well made, its your call into which you think its appropriate for your setup,

Mean Well Power Supply 12V 80W 6.6A
Mean Well Power Supply 12V 60W 5A
Mean Well Power Supply 12V 40W 3.34A

[LaserHosen]

Thanks, Abula.

They look the kind of thing I'm after. As for the drives spinning up, I think the timing of that will occur on immediate power on, whilst the BIOS is still booting and the CPU has yet to become loaded with tasks.

Would there be any efficiency advantage in going with the 40W one, I wonder?

[Abula]

Would there be any efficiency advantage in going with the 40W one, I wonder?

Hard to say, i own 2 of the 40W but i havent used them on PCs, they are on IR reflectors for my night illumination for my IP cameras. I have used the 60/80 on builds and i havent been able to see better numbers with 60, that said consumption is not static, so its very hard to judge.

Edit: Until now, i reread your initial post, and you are running 2.5 hdds, so it should have considerable less consumption, you might be able to get away with the 40W brick, if yo check my minimi build, i can idle close to 11W with one 2.5 mechanical, but the setup can reach above 40W on load, the main reason i went with 60W, but since you are using baytrail i think you might be fine with 40W, weather it has any discernible advantage i cant say, my guess is very little, but if that's your main goal.

[xan_user]

im no specialist... but i thought using a higher voltage, like 24v+ would be more efficient than 12v. isnt that why you got the wide input pico?
PS. any plans for a UPS?

[Vicotnik]

Since you have a wide input picoPSU, I would recommend any laptop brick you might have available. They are not hard to come by and are often efficiency class IV or V.

[quest_for_silence]

Since you have a wide input picoPSU, I would recommend any laptop brick you might have available. They are not hard to come by and are often efficiency class IV or V.

I would be cautious about a Level IV bricks, and about 19V inputs: sometimes they can be pretty low on efficiency (particularly when you compare them against Level V 12V ones).

IMHO an high quality 12V Level V brick should probably to be preferred for low level efficiency, but an available datasheet is pretty much mandatory to double check the expected figures, efficiency-wise.

[Vicotnik]

Of course, but 19V adapters are plentiful. I've picked up a few in the dumpster myself, some even rated V (often with partly chewed cords, but that's not a problem if it needs to be modified for the pico anyway). Good 12V adapters are not as easy to find.

[LaserHosen]

Those Mean Well ones are hard to find on Amazon UK. How about something like this?

The picture has V85 stamped on the label. Does this mean that it's class V and about 85% efficient?

[LaserHosen]

Well, after looking around I've chosen the 60W Meanwell one that Abula linked to.

Supplied by Baomain in China. so it's gonna take 10-12 days to reach UK but postage was very reasonable and the total cost was £16.18 for a class V power brick. The ratings look good and I'm prepared to wait, since I've been running the NAS on an inefficient 300W PSU for 3 months now, so an extra 10 days aint gonna make much difference.

Thanks guys, and thanks Abula.