# Track Snubber



## dspender

I just purchased an NCE DCC system. In the wiring discussion it states "also recommended onlayouts with long track bus or track blocks is a "snubber" wired across the bus or track. What does a snubber do? My layout is on a 4 X 8 sheet. I have two reverse loops. Do I need this?


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## Big Ed

dspender said:


> I just purchased an NCE DCC system. In the wiring discussion it states "also recommended onlayouts with long track bus or track blocks is a "snubber" wired across the bus or track. What does a snubber do? My layout is on a 4 X 8 sheet. I have two reverse loops. Do I need this?


I don't know but I did a search on a snubber and found this.
See if it helps a little. I couldn't find where snubber is mentioned though.

Edit.....,

I forgot the link.


http://www.mrrc.com.au/sse-012.htm


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## tjcruiser

Big Ed,

I'm not a DCC guy, but boy, that's an excellent link / resource you posted there ... great info.

TJ


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## Big Ed

tjcruiser said:


> Big Ed,
> 
> I'm not a DCC guy, but boy, that's an excellent link / resource you posted there ... great info.
> 
> TJ


I am not either. Just tried to bump his question because no one else did.

I am wondering what that means too?


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## tjcruiser

My only guess (and just that ... a guess) is that a "snubber" is simply a down-the-track direct wire lead back to the transformer, to minimize track resistance voltage drops over a long track layout?


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## Boston&Maine

I found this on another forum:



> The Snubber acts as a RC (resistor/capacitor) filter.
> 
> All of the power buss lines have noise on them and as the length of the power buss gets longer the noise gets greater.
> 
> When the noise gets too much the DCC signal gets lost in the noise and the decoder misses commands and you then think that there is a problem when in fact the decoder just missed the command due to the noise.
> 
> The Snubber bypasses the noise to ground (for lack of a simple explanation).
> 
> I had this problem on a 60 ft run and the engines would just runaway even with the keypad plugged in. The engine once started would not respond to any command. And it was only with certain engines. Others would work fine.
> 
> I also had problems with runaways on the other end of the layout but only after operating for more than 3 hours and then this would not always happen (so it was really hard to trouble shoot) change engines and it went away (which lead me to believe it was the engine decoders – but operated fine closer to the center of the layout – where the command station was).
> 
> Once I put the Snubber on the ends of the long Power Buss lines the problems went away and have never came back!
> 
> And this was on a Digitrax system not a NCE one! So this is not limited to just NCE.


I would say that you should not need one :dunno:


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## Big Ed

Boston&Maine said:


> I found this on another forum:
> 
> 
> 
> I would say that you should not need one :dunno:




Well..................as to what you posted I would say,



If your trains run fine with the command controller and you experience 
any of the above problem then you need to install it.

Me if it was my layout and if I had the "NCE DCC system" I would want one after reading that B&M.:thumbsup:
That way your guaranteed not to have any problems. As he says some engines work fine and others don't.

I glad know one else knows what it is makes me feel better.
I don't know much on this way of running a RR.
Though the more I read about it the more I want it.

Wait I will be right back..........

I'm hearing those voices again.................:laugh:

Got a hot bid going on e bay. Going to steal it at the last second.
I do it the old fashion way. finger on the buy button and eye watching the stop watch.



I did go to see my Doc about something else and mentioned the voices.
He told me to go with them as it keeps me home out of the bars and out of trouble.

And even with all the buying I do I am still saving on money considering what an alcoholic beverage cost today.
Not to mention tips to the girls!

My Old (young) lady likes it better to that I am home.
At least that it what she says.......................:laugh:


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## tankist

i run NCE and i'm not experiencing any problems yet. but i would guess that why bus wire should be twisted - noises inducted on the wire cancel each other out


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## tjcruiser

tankist said:


> ... bus wire should be twisted ...


Good thought ... you must know the tip here ... put a pair of wires into a drill chuck. Stretch and hold (or clamp) the other end of the pair. Turn drill on, and adjust wire tension as the drill does all of the work ... nice, tidy twists.

TJ


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## T-Man

The snubber sounds like a capacitor. A capacitor one or two are used to filter my DC power supply and protect the chips.


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## tankist

TJ, drill is not really needed since you want only 2-3 twists per foot tops .

guys, snuber is a device to compensate for sudden voltage spike that is caused by disconnection from inductive load. in most simple form it is the freewheeling diode that you put across terminals of turnout coils. perhaps there is something more complex for dcc. i don't use nayhting like that and all works fine


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