Structure POWER!

[tomikawaTT]

Of course, if:

• You're lighting every bulb on a model of the Las Vegas Strip...
• You're lighting every structure and street lamp on a major club layout built in a gymnasium...
• You don't mind depending on a single source for all structure lighting everywhere (with attendant high-amperage bus connections to the more remote locations)...
• You're actually buying your low-voltage power supply(supplies)...

Then a single computer power supply is probably a very good idea.

OTOH, if:

• You prefer to keep things de-centralized...
• You don't want house-wiring-size busses running all over...
• You aren't lighting that many structures and streetlights...
• Your collection of low-voltage supplies are either free or long since paid for...

Then the principle that applies is, "If it ain't broke, don't fix it."

In my case, I own a motley collection of toy train and obsolete scale power packs (40 ohm taper-wound potentiometer speed control, anyone?,) wall warts from dead power tools and other devices and a couple of filament transformers.  The plan is to power a single town from a single multi-outlet surge protector, and connect all the surge protector 120 cords to a single outlet strip powered from the 20 amp circuit that used to support the now-absent garage door opener.  If a single source item (wall wart or whatever) dies, I'll simply replace it with a like serviceable item from spares - and I'm sure I'll have PLENTY of spares.

Chuck (modeling Central Japan in September, 1964)

[UpNorth]

I can top  that. 10mb winchester MFM hard drives and assorted ram expansion cards that I can't for the heck of it remember the name of... They left last year in the "making room" blitz.

[jeffrey-wimberly]

500 meg hard drives?! Man, that's right up there with Edison's incandescent light bulb!

[loathar]

Yep! Now if I could just find a use for the pile of 500meg hard drives and 30 pin ram chips I have....

[UpNorth]

... Just eleven computer power supplies...  off the internet at $20.00 ...  another $10.00... jumped to say $330.00 total.

That should be 230$. So I just saved you another 100$... Too bad I got rid of my collected old computers and power supplies from my service years. had to make room.  

[jeffrey-wimberly]

Sounds about right. I've been using a computer power supply to run my layout lighting for araound ten years now. I recently bought another one (AT type) to have on hand as a spare as the one I'm using is getting pretty long in the tooth (it was old when I starting using it) and could kick the bucket any time.

Here's the one I just bought, new and still in the box for $10.

 

Nice thing about this type is that it's non-switching so it will run with or without a load. 

[Johnnny_reb]

My thoughts on power supplies for structures,

One amp = 1000ma

The three power outputs I plan to use on the computer power supply.

+3.3V at 28 amps output divided by a 30ma (load)  =  933 lights bulbs

+5V at 38 amps output divided by a 30ma (load)   = 1,266 lights bulbs

+12V at 17 amps output divided by a 30ma (load)   =  566 lights bulbs

                                                                   Totals = 2,765 lights bulbs

By dividing the total output amps of each power output, then divide by half again a computer power supply can easily power 1382.5 30ma bulbs at a 50% load on the power supply.

A one amp wall-wart run a full capacity can supply only 33.3 30ma bulbs and would need a total of 41.56 wall-warts to supply the same amount of bulbs as the computer power supply. Run it half capacity and you would need 82 wall-warts just to match the power output of the computer power supply. Wow at two wall-warts per outlet I would need 41 outlets. And I don't have 41 electrical outlets in my whole house let alone the train room.

So let say each structure on a club layout has 5 30ma bulbs and the layout has a total of 100 structures. That makes for a total of 15,000 bulbs. Just eleven computer power supplies would be more then enough to supply the power needs of the whole layout structure lighting system.

Edit: So let say each structure on a club layout has 5 30ma bulbs and the layout has a total of 100 structures. That makes for a total of 500 bulbs. Just one computer power supply would be more then enough to supply the power needs of the whole layout structure lighting system.

So one computer power supply ordered off the internet at say $20.00 each. Now add in the home engineering for the terminal blocks, computer power splits just to get you to the point of layout wiring. Lets say another $10.00 and the cost of using a computer power supply has jumped to say $330.00 total. Verses 82 wall-warts at $10.00 each for a total of $820.00 plus terminal blocks $3.00 each. For a total of more then $823.00.

Edit: So one computer power supply ordered off the internet at say $20.00 each. Now add in the home engineering for the terminal blocks, computer power splits just to get you to the point of layout wiring. Lets say another $20.00 and the cost of using a computer power supply has jumped to say $40.00 total. Verses 82 wall-warts at $10.00 each for a total of $820.00 plus terminal blocks $3.00 each. For a total of more then $823.00.

My time to build the layout lighting system (oh wait that's with either system). The cost of supplying power is $0.022 per bulb building the computer power supply interface system and $0.055 per bulb with the wall-warts and inter face system.

Edit: My time to build the layout lighting system (oh wait that's with either system). The cost of supplying power is $0.08 per bulb building the computer power supply interface system and $1.646 ($1.64) per bulb with the wall-warts and interface system.

So that's $30.00 verses $60.00 or more. I'll be using a computer power supply to meet my power needs. The way I see it, for my small layout one computer power supply and I'm good to go.

Edit: So that's (PC power supply) $40.00 verses (wall-warts) a $100.00 or more. I'll be using a computer power supply to meet my power needs. The way I see it, for my small layout one computer power supply and I'm good to go.