Streetcars in North America Streetcars in North America Electric streetcars or trolley(car)s (North American English for the European word "tram") were once the chief mode of public transit in hundreds of North American cities and towns. Most of the original urban streetcar systems were either dismantled in the mid-20th century or converted to other modes of operation, such as light rail. Today, only Toronto still operates a streetcar network essentially unchanged in layout and mode of operation. Older surviving lines and systems in Boston, Cleveland, Mexico City, Newark, Philadelphia, Pittsburgh, and San Francisco were often infrastructure-heavy systems with tunnels, dedicated right-of-way, and long travel
Electrical wiring in North America condition of use (suitable for dry and damp locations) for electrical wire and cable. Wire with THWN or THHN insulation is commonly used in the AC electrical distribution systems throughout North America, usually at voltage levels from 110 to 600 volts. This type of insulation is used for both copper and aluminum conductors which are either solid or stranded, depending on size. Many wires are rated both THWN and THHN, and are suitable for use in dry locations up to 90°C (194°F), or wet locations up to 75°C (167°F). Electrical wiring in North America Electrical wiring in North America follows