When a crane or any part of it's rigging and load contact an energized power line the electricity will use the crane or any person in contact with the crane, rigging or load as route to earth.
Damage can occur to any person or object that forms the route to earth. People can obviously be seriously injured and likely killed. The crane lifting line must be replaced( as required in the new crane and derricks law), the crane,s control systems could be destroyed and even the crane could be destroyed through fire.
To optimise the protection to both crane and personnel fit both an insulating link and a tag line insulator. As illustrated under all contact scenarios the rigger is protected from electrocution by either the insulating link or the tag line insulator and in some scenarios by both devices. However in some contact scenarios the crane is also protected by the insulating link.