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
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 $10.
Nice thing about this type is that it’s non-switching so it will run with or without a load.
That should be 230$. 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.
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.
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?[(-D],) 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.
Since we are playing “Can you top this” I have stored away with the manual my son’s first computer, a Radio Shack TRS 80 with a TAPE DRIVE. The monitor was built in the case as was the key board but don’t ask mehow many megs are on a tape… Some day it might be worth something.
I remember those “trash 80’s” [(-D] I got a Commadore 64 with tape drive for a graduation present back in 83. I later got a Commadore 128. It had some kind of railroad program for it that was all text. No graphics.
I have a question relating to power supplies so I guess it’s ok to ask on this thread. When you use a wall wort do you just cut off the plug end of the electrical cord and wire it straight to a bus for the structures. I kwnow next to nothing about electricity so I have to be very carefull. And Lothar, I believe the Comodore was one of the more advanced computers of it’s day.
In answer to your question, yes. Before I switched over to a computer power supply I used wall warts. I would simply cut the end off the cord and wire it directly to whatever I needed power for. And some Commodore 64’s and 128’s came with tape drives at the users option.
Yes. Light bulbs don’t really care about polarity but LED’s do. Watch your voltage. LED’s require around 3volts. Light bulbs can be from 1.5v. to 14v or more. You can use a 12v wal wart, just use resistors in line to step down down the voltage to what you need.
The Commodore 128 had dual 5 1/4" floppy drives and 2 megs of ram! State of the art!![:P]
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.
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 comp
Circuitron recomends the following wall wart which is also available from Radio Shack. I don’t know what the cost is but for me it would be simpler than a computer power supply to install as it is basically plug and play. Having already experienced two “good shocks” in my life time I do as little wiring as possible. If I can’t see it I don’t fool with it.
110 volt AC wall plug adapter outputs filtered 12 volts DC at up to 500 milliamps of current. Sufficient to power up to 30 TORTOISETM Switch Machines.
Something similar for lights with a 10/12 volt resistor as mentioned by Lothar should do on my size layout.
Nothing to do with the thread topic, but the Commodore 128 had but 128K of RAM, hence its name. Similarly, the Commodore 64 had 64K of RAM. The disk drives for the C64 were stand-alone 5.25" units (140K each disk) that operated off a proprietary bus, that the C128 also used. I don’t remember whether my C128 had an integral disk drive or not, but I know I used 3.5" 720K floppies with it. Also, got a 1200 baud modem, instead of the 300 baud with the C64. The biggest improvement was the 80 character display (640x480) instead of 40 characters. Cooking with gas! In 1993, I upgraded(?) to an Amiga. Finally, in 1997, I bit the bullet and bought into Windows.
Still have memories of writing Unix scripts and Pascal and Fortran programs to run on the Vax’s at Purdue with my C64, all from home with the 300 baud modem. Them were the days.
I know, I know… They would rather spend $15.00 for .5A to power 30 Tortoise instead of spending $10.00 to power ALL the Tortoise, all layout building lights and what ever else they can throw at it. And since the AC side is in a sealed enclosure that you simply plug a molded cable to, little to no danger of catching one big AC shock.
Basicaly what you are getting is something similar to the Digitrax PS2012 that sell for 150$.
