Check this out! I work as a hobby on private rail passenger cars and in some of them they use 120v 3ph corner grounded delta. All of the 120 volt circuit breakers are 2pole when you check pole to pole the meter reads 120v 2 of the poles will read 120 volts to ground (in this case car body) and the third phase will read 0v to ground. After doing commerical and industrial work for 30 years railroad electric can be strange.
