That would be charging up the spring to throw the breaker. High voltage breakers need to switch on (or off) very quickly, to avoid damage from arcing. It's common for them to have some kind of spring or gas piston arrangement that you pump up first to give them enough energy to do that quickly.

Nice attention to detail by the filmmakers.

No, he's winding up a spring to close the circuit breaker quicker than a human hand could, which reduces/prevents and arc from forming as the electrical contacts close.

How did you remember this scene?!

Hold on to your culos.

Ah shit now I want that panel for my dream house