Casing of electrical device

A casing of an electrical device, the casing comprising:

• a housing that has conductivity and has an opening;
• a cover that has conductivity and is configured to close the opening;
• and
• a gasket that has non-conductivity, wherein
• the housing includes
• a housing surface,
• a cover base that surrounds the opening and protrudes from the housing surface, the cover base including a first seat surface that is a top surface of the cover base,
• a pin base disposed adjacent to the cover base and protruding from the housing surface, the pin base including a second seat surface that is a top surface of the pin base,
• a positioning pin that protrudes from the second seat surface, and
• a groove that is provided between the cover base and the pin base and separates the second seat surface from the first seat surface,
• the cover includes a cover main body and a positioning tab that extends outward from an edge of the cover main body, the positioning tab being provided with a positioning hole,
• the positioning pin is configured to fit into the positioning hole,
• the gasket is disposed between the first seat surface and the cover main body,
• the gasket is a liquid gasket that has fluidity before being applied to the first seat surface and hardens after being applied to the first seat surface,
• the positioning tab is in contact with the second seat surface, and
• the cover and the housing are electrically conductive via the positioning tab.