After the electrification of Ofotbanen in 1923 NSB had been using El 3 and El 4 stock on the line. But in the 1960s these were getting worn out, and NSB decided that it needed to get new stock. NSB first acquired the El 12 stock parallel to the Swedish acquisition of the Dm3 locomotive. But unlike Statens Järnvägar, NSB chose to instead buy a newer technology locomotive from ASEA, based on the RomanianCFR 040. Thus NSB managed to get the same power out of their two-engined El 15s as the Swedish got out of their three-engined Dm3s. Since the locomotives were to be operated in pairs, NSB considered only installing driver cabins on one end, but chose in the end to install them on both ends to allow the locomotives to operate more flexibly, including allowing them to operate passenger trains. The locomotives were numbered 15 2191 to 15 2196.
In 1996 the operation of the ore trains was taken over by Malmtrafik, owned by NSB, SJ and LKAB, the owner of the mines. The new company ordered 18 new IORE locomotives from Bombardier and in 2004 the ageing engines were sold to Hector Rail.