In Captain America: Civil War the main antagonist, Helmut Zemo, uses a device to disable an electrical substation.
What is that device called?
It's a device for generating an EMP (Electro-Magnetic Pulse)
An electromagnetic pulse (EMP), also sometimes called a transient electromagnetic disturbance, is a short burst of electromagnetic energy. Such a pulse's origination may be a natural occurrence or man-made and can occur as a radiated, electric, or magnetic field or a conducted electric current, depending on the source.
Such devices can vary in size from small hand-held devices to large "guns" and, for the purposes of the movie, large area devices.