New NCE Snubber

Over the last couple years in Model Railroader, my wiring book, and on this website I have talked about using snubbers to protect against voltage spikes on the track created as a result of intermittent shorts and inductance. In those I showed how to build your own snubber based on a design suggested by Jim Scorse at NCE. Now Jim has come out with a ready to install circuit board version of the snubber that you can install into your existing wiring. His design is flexible in that there are a couple extra solder pads in case you want to experiment with additonal capacitors and resistors. Below is his description of the circuit and its use–just click on it to enlarge and save it to your computer. For those of you wanting quick and easy protection againt voltage spikes on your layout here is a ready to roll solution. MSRP is $12.95 for a pair of them.


  • At present time, I am only using one NCE Power Cab to power my layout. What something like this be of any use to me? Thanks

    • Not likely. Your booster output amperage is too low to be of any real concern. Just keep your bus runs under 30’and/or twist your wires (or use zip cord) as NCE suggests and you’ll be OK.

  • Michael Denoncourt

    Sorry I mismanaged the wordpress page and need to re-instate “follow”

  • Michael Denoncourt

    Larry, I am contemplating 4 power districts on my layout (using digitrax PM42 and the 8amp DCS 240 which they recently introduced). What would be the correct location to install a or several snubbers in this configuration?

    Thanks for what you do!


    • Mike–be aware that Digitrax does not recommend snubbers, just twisted pair wiring. That said I have a DCS240 and DCS200 with a PSx4 and a PM42. I use a home made snubber at the end of each power district power bus.

    • Hello Michael,
      I have a Digitrax medium small layout. I had a PM 42 for some time, but then got introduced to the PSX series of circuit breakers that Larry mentioned in his reply
      If you have not already purchased the PM4, I would suggest looking at the PSX breakers. I have the PSX-4, which is 4 circuit breakers. You can buy any amount you need, either single units, or multiple.
      These PSX units will do a lot more than the the PM4, which is why they cost a lot more.
      I built some drawer units for a friend utilizing a PSX breaker in each drawer, along with switches, wiring etc for a designated section of track it would control. I installed a folding front panel on each drawer which contained the control switches. Also a small sub panel over the front panel with lights and switches just for the PSX unit.
      There was a green LED lit, when power was on, A Larger Blue LED to show when there was a short, a push button to reset the breaker to on, after the short was found, and finally a switch to turn on pwr to the PSX and track section.
      On my own layout I also installed a small alert speaker, that gives you an audio warning in case you don’t notice the blue LED. I used a flashing LED on my layout.
      So all these things are possible with the PSX, and in addition you can fine tune when you want the breaker to trip.
      You can get info on the web concerning these breakers, and no, I don’t have an interest in the company, I just think they make a great product.