SJ Mg

Infobox Locomotive
name = Ma
powertype = Electric


size =
caption =
builder = ASEA
builddate = 1944-45
totalproduction = 17
uicclass = Co'Co'
gauge = RailGauge|sg
wheeldiameter = 1,000 mm
length = 16,800 mm
height = 4,500 mm
weight = 102 tonnes
topspeed = 80 km/h
electricsystem = 15 kV 16⅔ Hz AC
collection method = Pantograph
poweroutput = 2,640 kW
tractiveeffort = 300 kN
railroad =
roadnumber =

Mg is an electric locomotive used by Statens Järnvägar of Sweden for hauling freight trains. It was built in 17 copies by ASEA and was in service until 1980.

The Mg-series was built for the electrification of Norra Stambanan in the 1940s. It was steeper and more curved than the main lines in Southern Sweden, and single track sections meant that long freight trains had to be used to make best use of line capacity. The D-series was not powerful enough and the Of-series was to long for the curves. But as experience of the building bogie-locomotives increased, a Co'Co'-design was chosen for Mg, as the first bogie-locomotive in Sweden. More power also meant that the direct current motors from the D-series had to be replaced with the alternating current motors of the F-series. The machine room was not symmetric, so the loco was not the same on the right and left side. Mg was the basis for the Ma-series built in the 1950s.

External links

* [http://www.jarnvag.net/lokguide/Mg.asp Järnväg.net on Mg]