TVS - need help from ADCX Rob

The TVS diodes are to deal with inductive voltage spikes not over current situations like a derailed train. A circuit breaker or fuse will protect your wires from burning up provided the wires and circuit breaker/fuse are sized correctly.

The TVS diodes would protect your electronic equipment in just such a case. They will not protect wires or transformers - that is the job of the circuit breaker.

The more imminent problem is that it sounds like you are using the stock FasTrack wire leads to power the track - you have to upgrade to heavier gauge wire if you are using larger than a starter set transformer.

Even if you had the TVS diodes installed, they would not have kept your wires from frying. Only a fast acting circuit breaker would have prevented the meltdown. The circuit breaker in the ZW is very slow. Perhaps the ultimate in circuit breaker protection is here.

The TVS units will protect electronics from a voltage spike, not a short circuit.

Larry

That's subjective. The breaker in my 1949 ZW worked just as fast as it needed to(at specification) on my Christmas layout this year, and saved itself and all the wiring more than once during the season.

Thanks!  Yeah, I have always used much heavier gauge wire with my permanent layout and tubular track but (stupidly, naively) just hooked up the wires that came with the fastrack for the Christmas layout.

Where does one get connectors that hook onto the terminals on the underside of fastrack?

So, assuming I use properly-sized wire with PW era transformers, it still sounds like I still ought to have external circuit breakers if I'm running PW locos.  And, additionally, I ought to add TVS diodes if I'm going to run modern locos with TMCC or electronic whistles or e-units.  About right?

About right!

  Internal thermal breakers should work within spec, or changed IMHO.

   External breakers added as a "bonus". The amps for each matched closer to each individual tracks expected draw. PW, or new, your breakers are your amperage protection.

   A TVS protects new age semi-conductor components from voltage surge.

Sounds right now!

The .110 connectors for FasTrack can be sourced economically HERE.

Thanks guys.  Despite being at model railroading for about a decade, I don't put enough time into the homework part.

I've purchased some Lionel powermasters for the new layout to allow me to control track voltage from the Cab-1.  Do they eliminate the need for circuit breakers or TVS diodes?

No.

they are .110 quick disconnect terminal. I believe autozone has them if you need a few right away. I usually buy them on eBay by the 100 for a good price. Get them to match the gauge wire of course. At least 16awg.

Thanks again everyone. 

For what it's worth 16 gauge wire should be good with a post war transformer and an 8 amp circuit breaker added on the A to D terminals, one for each terminal.

FYI; the post war ZW has a 15 amp breaker on the common side and will take a few seconds to trip and will burn up wires if low in size.

Lee Fritz

It's easy to remember. 1) The circuit on your transformer(s) protect it only. 2) You need fast blow circuit breakers on each of your track feeds from your transformer(s) 3) You will need a TVS on each of your track feeds. One side of the TVS connects to the track feed, the other connect directly to ground. Remember to purchase bipolar TVS's. 4) If you have the room. You can install a TVS in each of your command locomotives for added protection.

God Bless,

"Pappy"

Anyone have pictures of how they've connected TVS's to their track feeds (transformer or powermaster)?

Not mine, I believe it's Dewey's... this is the barrier strip at the end of a PowerHouse lead(connector cut off):

Noting that you need bipolar TVS diodes, you can connect them directly across both terminals of your track lockons, or directly across the ZW transformer terminals (A-U, B-U, C-U. and/or D-U).

Larry

You could add a TVS to individual locos, and be protected on other layouts too.

These are good fast circuit protectors. Very fast.

http://tonystrains.com/product...ent-circuit-breaker/

Based on my read, I'm not going to need external circuit protectors for my soon-to-be-rebuilt permanent layout.  I'm installing a power master between each transformer and track/block.

I will get the circuit breakers for the Christmas layout next year.