The Three-Power Boxcab was developed in the late twenties for operation on both electrified and non-electrified lines in regions which prohibited the use of steam locomotives. When they worked on electrified sections, they could pick up lineside direct current, while primarily using battery power on non-electrified sections. The batteries were charged by a small diesel engine that could be switched off when running through stretches which even did not allow diesel fumes.
These locomotives were built by ALCO with electric components from General Electric, engines from Ingersoll Rand and batteries from Electric Storage Battery. The prototype from 1928 had a central cab, while the production locomotives had two end cabs. While the maximum output in electric mode was 1,580 hp, the 300-hp engine could only slowly recharge the batteries with a 200-kW generator. The batteries had a total capacity of 301 kWh, what meant that a complete recharge required one and a half hours with the diesel running at full power.
The locomotives were also called “oil battery electrics”, since the name “Diesel” was unpopular in the USA in this period. From 41 locomotives built, most went to the New York Central as class DEs-3. One went to the Rock Island and others to Chicago, Detroit and Boston. Most were equipped with contact shoes for 600 V DC, but two instead with pantographs for 3,000 V DC. Most were retired in the sixties and seventies.