The property has turned off the single-family switch. Can the host turn on the switch at home?

Theoretically there would be no electricity.

The main door is the main switch of the home circuit. If the main brake is pulled down, the whole house should be dead. For normal circuit installation, the master switch must be a 2p switch, that is, a circuit breaker that can cut off the neutral line and live wire at the same time. If only one line is cut off, it is unqualified.

If the main switch is a 2p circuit breaker, electricity can still be measured when the main switch is closed, then the main switch is broken and must be replaced.

If the main brake is a 1p circuit breaker, it can be determined that the main brake controls the zero line, not the live line, so the installation is unqualified. 1p circuit breaker can only be installed on the disconnection line, and it must be the control fire line. The master brake must be replaced by a 2p circuit breaker, and the zero fire line can be controlled at the same time.