What power source do you all recommend for powering my control panel that includes green/red LEDs, SPDT toggle switches that are connected to tortoise switch machines?
Craig North Carolina
I use an MRC Railpower 1370 DC power pack for a situation similar to yours.
Rich
Alton Junction
Where do you find them and how much do they cost?
Aikidomaster Where do you find them and how much do they cost?
$39..99 at MB Klein.
I have several but each one easily powers at least 15 Tortoises/DPDTs/Bi-polar LEDs/Trackside Signals.
http://www.modeltrainstuff.com/SearchResults.asp?Search=railpower+1370&Search.x=10&Search.y=15
LION just answered the Tortoise Control question just a few days ago. GO HERE and scroll down to my post, that sure beats posting all of those diagrams again!
ROAR
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Here there be cats. LIONS with CAMERAS
i use a 1 amp transformer (wallwart) available at Radio Shack for about 20 bucks. power 18 torti with bi-color leds. works fine. If you hunt you you can find the wallwort for a few bucks. I use the 9 volt variety so the tortoise runs a bit slower and quieter.
What I like about a power pack like the MRC Railpower 1370 is its versatility.
Besides being used to power such things as Tortoises, toggle switches and LEDs with DC power, the power pack has a variable speed dial to increase or decrease voltage, a directional control switch if you want to use it as a DC power pack for locos, AC outputs for accesories, and an automatic circuit breaker.
As with anything, you get what you pay for.
I use a 9-volt wall wart. It came out of the wall-wart box in my workroom. It probably came from an old cell phone. I only use it for the Tortoise motors themselves. I power LEDs from a different supply.
It takes an iron man to play with a toy iron horse.
Keep in mind its not the voltage but the amps that you need to worry about. Tortise will run on as low as 3 or 4 volts. You can get walwarts that run variable from 1.5 to 12 volts on a selector. So look at the MA rating of your LEDs and the Tortise. Now also remember most walwarts are not regulated meaning if they say 9 volts they could be putting out 12 volts and onl\y 9 volts when they are used at their max load..................this goes for any cheap power pack .Battery packs like for Laptops which are good to pickup used are regulated meaning if it says 12 volts its 12 volts under any load. Walwarts with a rating of 500ma are great for running as number of Tortise and control panel LEDS. So the resistor you use for the LEDS will be determined on the MA of walwart and how much you load it up or take the voltage of the walwart with no load play it safe and use that to calculate your resistor.Remember to all LEDs are rated differently so if you pick up a bunch make sure the MA rating and forward voltage is provided. If you get walwart with switched voltage from 1.5 to 12 volts you can play with the speed of throw you might like. I believe i am running 7 volts. I have a nummber of control panels and use a seperate walwart for each one.Steve
The amp output of the power supply has no bearing on the size resistor used for an LED. the only thing that counts is the current rating of the LED and the VOLTAGE of the power supply. The only thing the current capacity of the power supply determines is how many such loads you can connect to it. A 1K resistor on a white LED witll draw somewhere around 9ma. It doesn;t matter if the power supply is rated at 100ma ot 100 amps, if it's 12 volts, it will work.
Now, those larger numbers (like using an old PC power supply with 3 amps or better on the 12V side) are not something you want feeding unprotected into low current circuits, at those current levels it WILL melt the small size wire normally used for such things, but that's a different issue.
Same with Tortoises. They draw about 15ma each when stalled, less when running. That's why you can wire LEDs in series witht he motor power for indicators, 15ma is below the max rating for nearly every LED (at least the common ones anyone would normally be using) so the LED is protected without using a resistor. Each Tortoise draws 15ma. 10 of them is 150ma. Any power supply larger than 150ma (really should add another 25% so that the power supply is never loaded to 100% constantly) will work. 200ma. 500ma. 10 amps. Again, when the power supply is significantly higher in current capacity than the intended load, you should break it out into multiple circuits with individual fuses rated closer tot he intended load.
--Randy
Modeling the Reading Railroad in the 1950's
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The amp rating determine how much you can load it up! Thats what my point was. 500 ma will run many Leds and Tortise.Leds and Tortise have power to them all the time so for sure the amp or ma tating counts. Many commom walwarts are 500 ma even the one sold by circuitron for Tortise and that will run many LEDs and Tortise. There are many ways to wire Tortise i prefer not to wire the LED to the Tortise but seperately. For my control panel i use bi polar LEDs so i have always a green and red LED on at same time depending which route switch thrown. Seems to me you still need to add up the total of the ma of all LEDs on the panel. You can of course lower the brightness of LED with different rated resistor. Lotes of fun.Steve
Just the other day I attempted to use an old MRC Tech 2 Railmaster transformer to power my tortoises, but the 60 cycle buzz from the tortoises at stall was unbearable. Circuitron support suggested I use a 12V DC output desktop switching power supply. Since I'll eventually be operating 30+ tortoises each with a bi-polar LED for panel turnout indication they also recommended the power supply be 1 amp. minimum.
Regards, Peter
Oops, forgot to mention that I want to use the bi-polar power supply set-up for my tortoises, Circuitron support suggestion was two 12VDC output 1amp desktop switching power supplies.
regards, Peter
Tortoises at a full 12V are kind of loud, but usually not excessively so. If you used an old power pack turned up to near maximum, with the light load of a Tortoise or 2 is was probbaly putting out well over 12V.
If you are putting indicator LEDs in series witht he motor leads, that will drop the voltage to the Tortoise motor down to about 10V from a true 12V power supply. That will quiet them down. 2 sets of LEDs (one on the panel one one trackside) will drop down to below 8 volts, that's about as low as you want to go.
If you aren;t going to put the LEDs in series with the motor, and instead use the contacts to switch them, you probably want a 9V supply not 12V, for the same reason. To make them run quieter.