# Replacing a bunch of 12 Volt wall-warts...



## Nik (Jul 19, 2008)

Anyone dared replace their PCs' flock of 12 Volt wall-warts with a single 5 Amp PSU ??

I've got five (5) six-way power strips under this desk, barely 3 vacant sockets due overhangs, and several more widgets due soon...

I reckon I might be able to free 3 sockets plus their overhangs by combining the power supplies for wireless-router, twin NAS boxes and a planned switcher-hub. I'm not sure about KVMs as they're on other side of desk. 

Yes, I'd put 'hum-dinger' ferrites on those 12 Volt leads...


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## Highlander II (Jul 19, 2008)

I can tell you right now that all of that just went over my head. =)

I mean, I know what you're talking about on a very basic, generalized level, but the specs - not so much.

Though, there are several of the 'more techy' types who, I'm sure, know exactly what you're talking about and will toss in their 2c. =)


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## Nik (Jul 19, 2008)

*D'uh...*

It all began when the new versions of my favourite 3D software would not install without 'phoning home' to validate their licences...

Until then, my dual-screen 3Gb/3GHz CAD#2_PC was *strictly* stand-alone: I had a basic USB link for whizzing files to/from this paranoid Browser_PC, but no networking, so no fire-wall, so no great chunk of processor power stolen...
Bliss/

I tried using Window$' Internet Sharing, but this Browser_PC's firewall would not protect linked PCs. And there were other problems...  

So I needed a router. My desk's PCs would be 'cabled', but I bought a wireless router so guests could have a WiFi hot-spot.

Then it got hard. 
My ISP uses dynamic addressing. Sadly, neither the router's quick-guide, nor 'Dummies' Networking & Wireless Networking books had much to say on the subject. After laser-printing entire PDF manual and re-reading it for a week, I found the Sitecom router was actually, very, very easy to configure and secure. So easy, in fact, that I even managed to wireless-enable our old lap-top...

( Getting WiFi range further than I could throw lap-top is another story, as yet incomplete ;-)

Well, when you have a router, thoughts naturally turn to networked storage. I bought a pair of bare boxes, installed a 320Gb IDE drive in each, set jumpers to 'master', had twin NAS drives. 

Besides backing up PCs and each other, they'd have the capacity to down-load and store our family photo-albums. For output, I'll get a nice all-in-one HP scanner/printer with USB and network support, individual ink-tanks and PictBridge, one-touch copy etc etc...

Have you been counting ? Yes, I've filled all the ports on the router. I need a switching-hub, too. That will also let me connect the lap-top directly, and port files from my old Win'98 CAD#1PC rather faster than the USB cable allows...

And, yes, each widget needs a wall-wart, so add another power-strip. Of course, when you have spare power-points, those attract cordless screw-drivers, the external DVD re-writer, the laptop charger etc etc...

D'uh...


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## Erin99 (Jul 20, 2008)

I hooked up my dad's printers to his PC, then just added the two as a network prnter on my PC via my wifi connection. Sure, it means I have to switch on his PC if I want to print, but I can live with that (plus, the wall socket is in the next room, so I'm not innundated). And I wouldn't try putting too many power-hungry equiptment on the same wall socket, unless you have one of those snazzy extension power adapters that allow you to switch off each appliance on it.

Just try your test and see. Don't plug in everything at once, and take care not to overload the mains power.


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## Wiglaf (Jul 20, 2008)

I know nothing about combining power supplies or your amp draw. However, residential recepticles(US/Canada) can handle 15 amps through the plug and 20 amps pass through on the device. The wiring and breaker is probably 15 amps for all loads on that circuit. The real scary part and what might burn down your home is that loose connections cause tiny little arcs that slowly build up heat which wears away the metal and creates bigger arcs and more heat. The cycle ends when it all finally burns up. You have a much greater chance of a problem with a rats nest of plugs and wires under your desk.
The UK I believe uses 240v(rms) 50Hz.  I can't seem to find anything definative on amperage but I think they are rated 250v and either 10 or 20 amps.  I am guessing 10 as this would be equivalent to a North American 20 amp recepticle (120v * 20a=240v*10a=2400va)


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## Nik (Jul 20, 2008)

*Mains draw...*

Hi, my entire system's current draw from 220/230 Volt UK ring-main is only a couple of Amps total. Each Amp provides 220 Watts...

Each power-strip has a fused plug. Anything with a wired plug rather than a wall-wart has a replaceable fuse in plug...

My problem is I have a bunch of widgets that all want 12 Volts, and each needs a wall-wart...

Annoys me to have several identical widgets with identical plug-top power supplies taking up multiple power sockets. 

IIRC, guitarists etc often have one 12 Volt power supply feeding multiple stomp 'FX' boxes...


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## Wiglaf (Jul 20, 2008)

2400va=2400w your probably fine there but I just don't like that many plugs and wires.  Would some place possibly sell a plug in step down tranformer with a distribution center?  I know that you can get the parts to hardwire a setup in your ceiling for low-volt controls; is there such a thing as a plug-in unit(Xfmr and panel but with bannana jacks or something)?


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## Nik (Jul 20, 2008)

Yes, that's the idea...

Something like *this* item, but up-rated, plus a nice PSU...
Maplin > 2.1mm DC Power Extension Lead Set

Um, from the wary replies, I don't think anyone's yet dared...

I suppose voided warranty might be an issue, too...

At least the NAS boxes' wall-warts stay cold when their boxes are off, so are not drawing significant power...


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## Happy Joe (Jul 23, 2008)

I only have one wall wart (ice cube power supply, it took me a moment to integrate your visualization); If it gets annoying I would install a plug and just power the device from my PC power supply (both 5 and 12 volts are available with substantial power and good regulation). ...Or a person use an old PC power supply as low voltage power source (a power brick so to speak).

I try to avoid devices which use the plug in supplies as they seem to be very energy inefficient.

Enjoy!


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## chrispenycate (Jul 23, 2008)

Problems you could have.
1 polarity of supplies – not likely, I haven't seen any negative logic in a long time.
2 non-ground referencing- generally analog interfaces like screen drivers, audio converters or video inputs.
3 ground loops – the probability of fridge clicks, thyristor buzz or other electrical interference being picked up on your data lines is increased; binding the power cables together so they all get the same inductive current, so the different apparatuses don't tend to get differing references.
4 voltage variation with changing load. This shouldn't be a problem, especially with a stabilised power supply. Most of the gadgets aren't using more than six of the twelve volts anyway so a minor fluctuation shouldn't bother them.
Connector incompatibility – aargh. I seem to have eighteen different standards here for getting twelve volt DC into things (no, nineteen, there's a Mac laptop on another. All incompatible, no standardisation of interior/exterior polarity on coaxial ones, no standards anywhere…


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## Happy Joe (Jul 24, 2008)

In the past when I needed to match power plugs (i.e. to run electronics when camping, or extended capacity battery pack for a video camera, etc.) a short trip to the electronics supply house some wire and solder (perhaps a bit of heat shrink) has done the trick.

Polarity?  Just verify it with your DVM (...everyone has at least 2 or 3 (...don't they?)).

Enjoy!


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## Nik (Jul 24, 2008)

In addition to several DVMs, I've got a tiny box with two LEDs that show polarity of supply. As an idiot-mistake trap, it is *superb*...


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