Lightning protection coil

Lightning protection coils were used on electric locomotives in the early 20th century .

purpose

The purpose of lightning protection coils was to attenuate a rapidly increasing contact wire voltage due to their high impedance for large voltage changes per period. Causes of such voltage increases can e.g. B. lightning strikes in the contact line or brief lifting of the pantograph from the contact line. This protected the step transformer and the engines of the locomotive , for example .

Other measures

However, experience showed that the benefit was not very high because the low resistance of the catenary system was able to dampen lightning strikes. Improvements in the insulation strength of the step transformers also meant that they themselves had sufficient impedance to be immune to lightning strikes.

After the installation of surge arresters and double rockers on the pantographs in the early 1930s, the lightning protection coils disappeared from the roofs of the locomotives.