How can I incorporate a instantanous circuit breaker into my layout

Circuit breakers, including internal transformer only protect the transformer, and not beyond the terminals of the transformer.  If your concern is to protect your loco electronics, you need to use a TVS (transient voltage suppressor), which protects beyond the transformer.  Search within this forum on the subject of using, and hooking up a TVS.  I can't add info with this post, ask am using an iPad, and not on a computer to give you links to search.  

You should be lucky you haven't fried anything else if it is of the newer generation with circuit boards, using that transformer.  Just my opinion

Search for PSX-AC or PSX-1AC, I think these will do what you want.

Adding extra TVS devices won't hurt either and will only add to your protection. They are inexpensive.

https://ogrforum.com/t...t-circuit-protection

Does/can you transformer put out more than 18V?

rtr12 posted:

Search for PSX-AC or PSX-1AC, I think these will do what you want.

Adding extra TVS devices won't hurt either and will only add to your protection. They are inexpensive.

I second this. PSX-AC.

In-line fuse holders and AGC fastblow fuses are simple. The 3 4 or 5 amp would be the range. AGC3, AGC4, AGC5. Have plenty of spares on hand.

Which transformer(s) are you using 19B, 22080 or 30B?  The "Deadman Handle" seems cool.

Dale, I saw a photo of the terminals of the 22080. That one is labeled as 18 volts.

I use 10A Airpax instantaneous magnetic breakers between the power (20A TPC 3000s) and the TIU or track. The supplier (Poco Sales) wondered why I was ordering instantaneous vs. fast acting as they were appropriate only when there were sensitive electronics downstream from the power supply. Exactly. In use, the breaker doesn't pop except for a dead short that draws a lot of amps. We're currently running a show layout on one of these which includes sparking across turnouts, and the breaker holds during normal running. The part is Airpax SNAPAX magetic-hydraulic breaker PP11-0-10.0A-OB-V Push-Pull (so you can use them as a block switch), instant trip 10.0A rated for 0 to 125V AC, 32V DC. I have tested samples at 10A continuous resistive load (until my load resister got way too hot) and found that they trip reliably before the load goes above 11 Amps. When the load is shorted, they trip instantly. Considering the long lead time for these special order breakers via distributors, the PSX-AC may be a better bet if it is readily available.