I want to know the answer to the following question:
When was a 11kV system of NY, New Haven and Hartford was converted to 12.5 kV?
All the background I'm provided with is that "The SEPTA power distribution system uses a 2:1 ratio autotransformer system, with the catenary fed at 12 kV and a return feeder wire fed at 24 kV. The New York, New Haven and Hartford Railroad used an 11 kV system between New York City and New Haven, Connecticut which was converted to 12.5 kV 60 Hz in 1987.". Is that enough to answer the question?
Answer: yes