SS7b Electric Locomotive

From: 2016-05-05

Introduction of the product:

SS7B electric locomotive is a kind of 6-axle freight electric locomotive of 4800kW with 25t axle load developed and designed on the basis of SS7 electric locomotive. It takes single-phase power frequency, voltage 25kV and AC-DC transmission. Startup at constant current + quasi constant speed is seen as its traction feature. It is equipped with devices for power factor compensation and electric compensation of axle load transfer. It is suitable for the mountain lines with sharp curves and long slopes. Several locomotives could be connected for use.

Main technical features:

1. The carbody applies frame integral bearing structure with double driver’s cabs and corridors at two sides.

2. Bo-Bo-Bo axle arrangement is taken for the bogie. It is made up of three 2-axle bogies, featuring short fixed axle distance and good curve passing-through performance.

3. Cabinets and modules are designed and standardized for the electric devices.

4. Being a shell integrated transformer, the body the main transformer shares the same oil tank and forced oil circulation air cool system with the smoothing reactors and power factor compensation reactors.

5. The main circuit applies voltage adjusting rectification with full control + half control double section bridge for the series excitation circuits of the traction motor while one section bridge for the separately excited circuits, making smooth stepless adjustment of speed.

6. The locomotive is equipped with electric compensation device for axle load transfer and anti-slip and anti-slide protection devices. The adhesion usage is good.

Main technical parameters:

Current system

AC 25kV  50Hz

Track gauge


Axle arrangement


Axle load


Tare weight of locomotive


Continuous power


Highest running speed


Continuous speed


Continuous traction force


Startup traction force


Electric braking way

Regenerative braking