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As of 2012, electrified tracks accounted for nearly one third of total tracks globally. The European Union contains the longest amount of electrified railways (in length), with over 114,000 km (71,000 mi) of electrified railway, what is electric cable however only making up around 55% of the total railway length. However, this limitation is being overcome by railways in India, China and African countries by laying new tracks with increased catenary height. Overall, China takes first place, with around 100,000 km (62,000 mi) of electrified railway, followed by India with over 60,000 km (37,000 mi) of electrified railway, and continuing with Russia, with over 54,000 km (34,000 mi) of electrified railway. Such installations are in the Western Dedicated Freight Corridor in India where the wire height is at 7.45 m (24.4 ft) to accommodate double-stack container trains without the need of well-wagons. In most of the world's railway networks, the height clearance of overhead electrical lines is not sufficient for a double-stack container car or other unusually tall loads. Due to the height restriction imposed by the overhead wires, double-stacked container trains have been traditionally difficult and rare to operate under electrified lines.

Several countries have announced plans to electrify all or most of their railway network, including Indian Railways and Israel Railways. The Trans-Siberian Railway mainly in Russia is completely electrified, making it one of the longest stretches of electrified railways in the world. P. M. Kalla-Bishop, Future Railways and Guided Transport, IPC Transport Press Ltd. As of 2023, the Swiss rail network is the largest fully electrified network in the world and one of only eleven countries or territories to achieve this, as listed in List of countries by rail transport network size. A number of countries have zero electrified railways, instead relying on diesel multiple units, locomotive hauled services and many alternate forms of transport. There are a number of advantages including the fact there is no exposure of passengers to exhaust from the locomotive and lower cost of building, running and maintaining locomotives and multiple units. The plug and socket replaced the BS 546 plug and socket, which are still found in old installations or in special applications. EN 50163: Railway applications.

Another aspect that can raise the cost of electrification are the alterations or upgrades to railway signalling needed for new traffic characteristics, and to protect signalling circuitry and track circuits from interference by traction current. In the same year Johann Schweigger invented the galvanometer, with a coil of wire around a compass, that could be used as a sensitive indicator for an electric current. His work was taken over and developed by Moritz von Jacobi who invented telegraph equipment that was used by Tsar Alexander III to connect the Imperial palace at Tsarskoye Selo and Kronstadt Naval Base. This was invented in 1930, but not available outside military use until after World War 2 during which a telegraph cable using it was laid across the English Channel to support troops following D-Day. NEMA non-locking connectors all use blades of various flat and folded shapes (except for the round pins used on grounding connectors). NEMA connectors are power plugs and sockets used for AC mains electricity in North America and other countries that use the standards set by the US National Electrical Manufacturers Association. Digital Museum of Plugs and Sockets. Moulded plugs for unearthed, double-insulated appliances may instead have a non-conductive plastic pin (an Insulated Shutter Opening Device or ISOD) the same size and shape as an earth pin, to open the shutters.

Brian Bilton. "Earth leakage protection unravelled". Wireless power transmission has been studied for transmission of power from solar power satellites to the earth. Power gaps can be overcome in single-collector trains by on-board batteries or motor-flywheel-generator systems. However, due to ventilation issues, diesel trains may have to be banned from certain tunnels and underground train stations mitigating the advantage of diesel trains somewhat. Most stepdown transformers are designed for single-phase operation; if a three-phase secondary circuit is required, three physical transformers are usually required, and may be mounted the same pole as shown in the photo above. Appearance: the overhead line structures and cabling can have a significant landscape impact compared with a non-electrified or third rail electrified line that has only occasional signalling equipment above ground level. This is done by the use of high voltage electrical testing equipment. In 2014, progress is being made in the use of large capacitors to power electric vehicles between stations, and so avoid the need for overhead wires between those stations. 1-15R receptacles have been prohibited in new construction in the United States and Canada since 1962, but remain in many older buildings, and this obsolete design is still available for repair use only.