Powering Tortoise Switch Machines & Accessory decoders for automation

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J

jtomai

New Member
Hi all,

My question is about powering Switch Machines and decoders. Whether its better to run them off the DCC Bus, or create a separate Accessory Bus & how to best go about that. Here are the details of my layout:

I just set up my first DCC system (NCE Power Pro 5 amp) it is currently powering about 150 feet of track with 16 turnouts which I plan to automate. Long term I plan on running a total of 6-8 trains on the layout.

Currently my 16 turnouts are totally non-automated. I am strongly leaning towards Tortoise Switch machines. So assuming I go with Toroise, I will need (2) of the NCE 524136 Accessory decoder which can control up to 8 Tortoise switches each. I've choosen not to build a toggle switch panels yet, but to run the switches using the NCE CAB and its Macros.

I understand how each accessory decoder gets connected to a switch machine, and the CAB can then control that switch via the accessory's address in the system.

Should I use my 5 amps DCC bus to power the Tortoise Switch machines AND the decoders, or should I run a separate Bus to power the switches? And if I run a separate accessory Bus, can I use my old MRC Railpower 1370 power supply to power it? It features 18va and an AC output for accessories. Or am I better off buying an Accessory specific power supply? Is there one? What brand and model should I consider? I could buy another NCE P515 5 amp power supply for my accessory Bus right?
 
jtomai said:
....I've choosen not to build a toggle switch panels yet, but to run the switches using the NCE CAB and its Macros.
Click to expand...

Very cool!

In addition to "Decoder Pro", JMRI also includes "PanelPro" - This allows you to build a virtual panel on your 'puter - Click the TO, and it'll get thrown etc - Wonderful stuff that completely negates the need for toggle switches.

I don't know about NCE kit, but suspect your stationary decoders should have their own power supply - I'm sure this is detailed in their manual?

Good luck, and congrats on the purchase!
Cheers,
Ian
 


NCE manual says that their accessory decoders can be powered from the rails, the DCC Bus or a separate power supply. I guess its a mathmatical function of my 5 amp DCC system vs the # of trains Im running and the # of turnouts with machines and decoders. For estimates I'd have 5 amps running say 6 trains (at 1/2 an amp each thats 3.0 amps) and 16 switch machines w/ decoders. The 16 switches and machines dont run until you throw a switch so Im imagining that the switches and their decoders wont take much power and only for the second or two they are in use. I mean, I wont be running 16 switches & decoders at once, let alone prolonged & concurrently!

Finally, each of the 3 districts in my layout will be isolated and feature its own 5 amp booster. Each section would only contain an average of say 5 turnouts?

More and more I think about it, Im just gonna run straight off my DCC Bus on district 1 as a guinea pig and see how it goes.
 
Actually Tortoise machines draw more power when they aren't moving than when they are. But it's pretty tiny either way. In your situation I'd do what you're planning, run the accessories off the DCC power. It doesn't sound as if you're anywhere close to overloading the system.
 
Yep you'll be just fine. I have the NCE PHP Wireless 5amp system like you. I have 24 switches with Peco switch machines and NCE switch-ITs accessory decoders, and I have absolutely no problems running everything of the DCC system track power.

With my extension room layout, I will have an additional 18 switches. So a total of 42 switches all being run on track power. I also use the macros for routing.
 
jtomai said:
Hi all,

Should I use my 5 amps DCC bus to power the Tortoise Switch machines AND the decoders, or should I run a separate Bus to power the switches? And if I run a separate accessory Bus, can I use my old MRC Railpower 1370 power supply to power it? It features 18va and an AC output for accessories. Or am I better off buying an Accessory specific power supply? Is there one? What brand and model should I consider? I could buy another NCE P515 5 amp power supply for my accessory Bus right?
Click to expand...

You might want to check out this web site.
http://www.wiringfordcc.com/sw_ctl.htm
 
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