Beginning with the modernisation of the Zagreb–Belgrade railway line an electrification system of 25 kV/50 Hz was used. Electrification on other lines in Croatia was then made exclusively 25 kV/50 Hz. Later, the majority of the Zagreb–Rijeka line was re-electrified to 25 kV/50 Hz, but until December 2012 there was still a part that under 3 kV DC. Consequentially a power system break existed at Moravice. HŽ was considering the purchase of dual-voltage locomotives, as an alternative to full re-electrification of 3 kV DC tracks, but the idea was scrapped for good as all electrified railways in Croatia are now using 25 kV/50 Hz.