The SB5 has built in over current sensing (500 milliseconds) for basic self-protection that will continuously try to reset every two seconds until destroyed if left uncorrected. It does not have a breaker that will trip or fuses that will blow.
The EB1 Circuit breaker provides automatic or manual short circuit protection (16 milliseconds or longer) for one power district. Can be used with most DCC systems. Threshold, Duration, type of reset can all be configured.
Features of the EB1: Provides short circuit protection for one power district. Trip current adjustable for 2.5 to 8 Amps. Easy hookup using screw terminals, no soldering. Status indication LED. Additional output for remote LED. Optional manual reset. Adjustable short circuit response time. Adjustable power-up response time to accommodate sound decoder equipped locomotives
Don't forget to use a REAL surge protector not a power strip. Example: http://www.apc.com/products/resource/include/techspec_index.cfm?base_sku=NET
The NCE part number for the EB1 is 5240225
To buy a new version of the EB1 direct from NCE click here