[3] Four years later, six bogie trailers were delivered from Hannoversche Waggonfabrik, which were somewhat smaller and had seats for 36 passengers.
The junction between the two networks was a 10-meter (33 ft) section without an overhead wire at Oslo Hospital.
[5] The two groups were connected so they were either serial or parallel connected, so each motor would either receive 300 V or 600 V. However, they were not connected to they would receive the same current in the city as on the hill section, thus the trams had only half the power when running on the 600 V section, with each motor either running at 150 V or 300 V. However, peak power was not needed, as the city was flat and had a maximum speed limit of 40 kilometers per hour (25 mph).
When the trams ran on the 1,200 volt sections, the switch connected pairs of series together.
[7] The oldest trams (1001–1005) controlled the motor current directly, through a slipring contact with five serial, four parallel and five braking steps.
The maximum speed of the trams were 40 kilometers per hour (25 mph) when running at 600 V and 60 kilometers per hour (37 mph) when running at 1,200 V.[9] The trams had dynamic braking, where the motors were connected so they acted as a generator.
During the 1950s, Oslo Sporveier started rebuilding the switches so that it was controlled by the tram, based on whether or not it was using power at a point.
1048 were delivered with a power cord to connect to the motor car, and some of the older trams were also rebuilt.
Along with 1002 (new), these were bidirectional with a driver's cab at both ends to allow the pendulum running on the Simensbråten Line.
All of the trams had a conductor, which communicated with the driver with electric bells and pulling of a rope.
From 1955, tram 1007 was converted to a maintenance car, including an extra compressor, larger air tank, and seats were removed to allow more space for tools, as well as a steering mechanism for the plow to allow it to be controlled by the driver.
[15] In 1931, 1003 was rebuilt with a width of 2.5 meters (8 ft 2 in) and a higher seating capacity.