Near silent build with DC UPS (no inverter!)

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Joined: Fri May 09, 2008 9:40 pm
Location: Australia

Near silent build with DC UPS (no inverter!)

Post by Elrast » Sat Mar 03, 2012 3:18 am

Finally did another build.

Its actually two PCs in the same setup, with a single AC/DC supply and battery backup. ... 470su.jpg/

The small boxes at the top are the KVM switch, a gigabit switch and a reflashed wireless router.

Each PC is inside a HDPlex H3.SODD case:

There's been a few HDPlex builds, so won't go into too much detail, other than to point out specific details:
* Its a intel DH61DL with a M2-ATX (wide input voltage picoPSU)
* M2-ATX has the nominally 12V leads running out of the H3 case in the rear
* Note the rigged up heatpipe going to the RHS of the case, touching the chipset (thanks Larry@HDplex for sending the additional heatpipes free of charge!)

PC1 is the mediaPC, has a 2.5" 40GB SSD (in hindsight, should have spent bigger and gotten at least a 80GB) + 2.5" 320GB HDD (to be upgraded in the future). This doubles up as the fileserver.

PC2 is the mainPC, has a 2.5" 120GB SSD. Only OS + programs are stored on the SSD.

Going back to the overall architecture:

Both PCs are hooked up to this battery charger (Iota DLS 30Amp), seen on the LHS of the below photo.
The core of the setup is of course the BIG 12v 100AH battery on the RHS.
Also note the very ghetto busbar arrangement!

The Iota DLS charger is a CV/CC supply. The attached blackbox turns it into a 3 stage charger, plus enough smarts to "refresh" the battery from time to time.

Power draw:
There's a Watts Clever plug-in monitor monitoring (only) the Iota charger. With both the mainPC active (typing this up) and the mediaPC active (7MC running in TV mode), the consumption is 73W.

Switching the media PC off gets down to 46W. Switching off the mainPC as well drops down to around 20W+, which is all from the Iota. Even if its not float charging the battery, idle consumption by the IOTA is still around 20W. Obviously I would like this to be lower, but data points on this type of UPS configuration is rare atm :S

As I progressively shift more of the complete system onto the UPS'd supply, the overall efficiency should creep up.

There's two rotating parts - the 2.5" HDD in the mediaPC - fairly quiet resting on a couple of sorbothane strips on the case bottom.
The fan on the Iota. Its supposed to be proportional to temperature, but seems to be on always? Anyway, a bit of clicking sound.
The Iota is generating a bit of electrowhine. PCs are ok.

Future improvements:
* Backup HDD through a USB3 port on the mediaPC
* Shift valuable data off the SSD and onto the fileserver. Maybe setup up an hourly sync or something.
* Get a high quality power board with arrestor + MOVs (both needs to be replaceable and have visible health indication)
* Replacing plugpacks on the gigabit switch and the router with a 12V -> 5V and 12V -> 9V DC/DC converter modules
* Consider switching over to a new main monitor that uses a plugpack; replace with a DC/DC converter module. maybe.
* Got a ST0180 coming as the replacement mediaPC monitor :)
* Rig up some kind of metallic contact between the RAM and the HDPlex lid - RAM is pretty hot. Or maybe a double bagged coolpack - incidentally have been using a coolpack'd HDD for a few years prior to this build, and it was working without a hitch.


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Joined: Mon Apr 02, 2012 7:08 pm

Re: Near silent build with DC UPS (no inverter!)

Post by chrispomeroy » Mon Apr 02, 2012 7:13 pm

This is great!

What are you using for motherboard power supplies? PicoPSUs?

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