What is the function of a consumer's main switch?

The main switch in a consumer unit is used to control the flow of electricity to the entire electrical installation in a building. It is typically used to turn off the power supply in case of emergencies, maintenance work, or when the building is not in use to prevent any electrical hazards. The main switch acts as a safety device to protect the electrical system and the occupants of the building from potential electrical dangers.

Isolate all circuits downstream from it, including all other consumer units.