Editing Overhead line (section)

=== Gaps ===
[[File:Spoorbrug Meppel - Buitenvaart, Jaagpad - 04.JPG|thumb|A [[swing bridge]] near [[Meppel]], the Netherlands. There is no overhead line on the bridge; the train coasts through with raised pantograph.]]

Occasionally gaps may be present in the overhead lines, when switching from one voltage to another or to provide clearance for ships at moveable bridges, as a simpler alternative for moveable overhead power rails. Electric trains coast across the gaps. To prevent arcing, power must be switched off before reaching the gap and usually the pantograph would be lowered.