And be sure to use at least 16 gauge wire when using 10 amps on your layout
I don't agree. For that amperage, I recommend 14-gauge.
I agree with PCRR/Dave to use breakers. I get mine from Defender Marine. Over the course of time, breakers are cheaper. I use external breakers on all transformers, for redundancy, and, by using smaller breakers, sized to cover maximum expected loads. They blow faster on a derailment. I find 5 amp & 7 amp to be adequate, butr don't use smoke