# Which power supply should I add?



## noela (May 22, 2008)

I am looking to add a power supply for my track powered layout. I like to run double headers, and would like a unit that can run 4-6 locos at a time. It would be a source supply, being controlled by Aristo Train Engineers. What would be the ideal voltage and current output for this power supply? Are there suggested power supplies out there that have been proven to deliver consistently? Does it need to be filtered? So many questions. Needless to say, any thoughts on this are greatly appreciated.
Thank you.


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## Greg Elmassian (Jan 3, 2008)

Noel, which Aristo Train Engineers? The original "Trackside" units controlled by 27 MHz? 

Those are (best case) 10 amps each. 

How many Train Engineers will run at the same time? 

Yes, the more money you spend, the higher quality components (usually) are in the supply. 

The answer to your filtering question depends on if you are running "linear" or the Aristo "PWC" which is Pulse Width Modulated. 

Keep adding information and we can refine the answer. 

Regards, Greg


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## noela (May 22, 2008)

Hi Greg, 
Thank you. 
I am running both types, with the 27 MHz for the freight yard, and two of the newer units for the loops. The one for the freight yard is on its own power supply, and the maixum I may run on the other units will be three (if I ever get the "Town" layout built). I will be using Linear power, rather than PWC due to the fact that some older units will be run on this layout. Hopefully this additional info can help in my selection. 
Thank you again. 

Noel


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## Greg Elmassian (Jan 3, 2008)

I would personally use separate supplies, but you can use one very large supply. 

The "newer units" are not trackside? Are they the Revolution units designed to plug and play? 

I would use 3 smaller switching supplies, like meanwells, rather than a single larger supply. If you used a 30 amp supply and had a 20 amp short, it would not shut down. 

The independent supplies would more likely let you take advantage of their own current limiting / short circuit protection. I think that you might find 10 amp supplies more competitively priced than a single 30 amp one. 

Regards, Greg


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## noela (May 22, 2008)

Greg, 
Thank you. I looked at meanwells, but will have to narrow my search. I've fused all three train engineers (5 amps for the yard, 8 amps for each of the loops). they are not the Revolution units (base station), but the older 55000 series with 10 amp capacity. With respect to 10 amp supplies, what voltage would I want? Do the meanwells maintain their current and voltage automatically? Do I need to concern myself with PWC? The reason I ask the last question, from what I understand, PWC is only good for the newer Aristo Engines. We will be running older Aristo engines, as well as engines from other manufacturers. the power supplies will be housed in a shed, so they are protected from the elements, and the wire from them to the track is in conduit. Once the power is turned on the power supplies, all we need is the hand held transmitters, no need to mess with 120 volts outside the shed. 
Again, thank you. 

Noel


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## Greg Elmassian (Jan 3, 2008)

I think the 27MHz Trackside Train Engineers have 24 volt max. I have not experimented with higher voltages on them. Perhaps someone can comment on this. 

I would run the 24 volts unless you are always running very slow. 

PWM (PWC is the Aristo term for the industry term of PWM) won't hurt anything you have EXCEPT some older sound cards don't like it. 

The Train Engineers have the linear / PWM-PWC switch so you can change it any time. 

10 amp Meanwells are fan cooled regulated switching power supplies and compact. Regulated means they hold the same output voltage regardless of load. 

The Aristo Elite and Everest supplies are regulated switching supplies also. 

Regards, Greg


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## noela (May 22, 2008)

Hi Greg, 
Thank you. 
You have opened up my island of ignorance. Shows to go you how much I don't know. You got me on PWC. I was running a Kalamazoo donkey on linear power, and wanted to see what PWC would do, so I switched over, and nothing happened. Nothing, meaning the engine did not move, and there was no indication that code signal was working either. When I switched back to Linear, it worked fine, again. Just exactly what does PWC do to the output that might cause this? Did I do something wrong? I also looked on the Meanwells site, but couldn't sift through what I needed. I assume I would be looking for a 10 amp, 24 vdc regulated power supply. 
Thank you again. 

Noel


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## Greg Elmassian (Jan 3, 2008)

If nothing happened when you changed to pwc, then you have a problem with your unit... That switch does not affect codes, or RF transmission. 

Try it on your other TE's. You can slide that switch any time. 

Yep 10 amp 24 volts... I use an 11 amp 27 volt, but that's because I run DCC. 

Regards, Greg


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