Do not use any type of breaker designed for standard AC or DC no matter the rating. The DCC signal is neither AC or DC. Using any product not specifically designed or approved for DCC should not be considered. includes any form of breaker designed to be used in a 120VAC circuit.
You can have a short circuit in a decoder but there is no guarantee it will trip a DCC circuit breaker or shutdown a booster.
Myth: DCC circuit breakers protect decoders.
Fact: DCC circuit breaker protect boosters.
The goal of the DCC circuit break is to protect THE BOOSTER by isolating the short locally within the breakers power district so the booster can remain powering the OTHER power districts to keep the other parts of the layout running.
For the DCC circuit breaker to act, a short circuit has to meet specific criteria.
a) The short circuit current must be above the trip point of the DCC circuit breaker.
b) The short circuit current must last for a period of time.
There is nothing in the design of a given decoder that is designed to comply with these requirements when they fail.