Class 'EM1' D.C. Electric

The success of the 1931 project to electrify the Manchester South Junction & Altrincham railway (briefly described here) encouraged the L.N.E.R. to proceed with their plans for electrification of the main line between Manchester and Sheffied but World War II delayed completion of this project. After World War II, the long-planned scheme introduced main line overhead electrification at 1500 volts d.c. The majority of the electrified line was opened by 1954. Freight trains were single-headed or double-headed by one or two of the original class 'EM1' Bo-Bo locomotives (later TOPS classification was Class 76). Passenger trains were hauled by class 'EM2' Co-Co locomotives (later TOPS classification was Class 77).

I was a volunteer at the Science and Industry Museum in Manchester (MOSI) for many years (you can find all my posts about the Museum here). A complete cab from an 'EM1' locomotive was displayed in the Power Hall at MOSI. However, on my last visit to the museum in 2022 (described here), many exhibits, including 'Ariadne' were not viewable because of a 'multi-million-pound restoration programme' in progress.


One cab of the ex-Manchester, Sheffield, Wath 'EM1' electric locomotive 76039 has been preserved in British Rail blue livery.


Ex-Manchester, Sheffield, Wath 'EM1' electric locomotive 76039 preserved cab in British Rail blue livery with later running number and worksplate


Driving desk of preserved cab. The reflections from the various surfaces produce a rather confused result, sorry.

The 'EM1' Bo-Bo locomotives had four 467 horse power Metropolitan Vickers d.c. motors. Pair of motors on each bogie were permanently in series. For starting, all four motors were in series with 15 starting resistors in series. 'Notching-up' progressively removed these resistors. The two pairs of motors were then placed in parallel with the starting resistors re-instated. Further 'notching-up' progressively removed the resistors. Final acceleration was achieved by weakening motor fields by switching-in a resistor. The drawing below includes the mechanical drawing, wiring drawing and control table.


Click for larger view
'EM1' Electric Locomotive (from 'Metro-Vick Locos 1954' in Railway Archive)

Related posts on other websites

British Rail Class 76 (Wikipedia).
The Electric Bo-Bo Class EM1 (BR Class 76) Locomotives (LNER Encyclopedia).


Related posts on this website

Class 'EM2' D.C. Electric