I hooked up some gauges around the first of this year just screwing around. One was a chronograph that tracks time only when my layout is powered up. It has logged 201 hours of train running time. That converts to 8 1/2 straight days of pure fun. I was very surprised especially since this does not count time building and fixing and planning things. I also have a gauge that tracks transformer tempertures. Crazy I agree.
I do not recommend getting one of these if your spouse thinks you spend too much time on trains. This instantly and solidly verifies it.