Combining several electricity meters in a network

And what is the difference between "separately" and "one by one"? Firstly, without breaking the seals and without the knowledge of the power supply, you do not have the right to change the connection diagrams of metering devices. They are established according to the contract. Explain normally, what do you want to do? The meters either count each room separately, or a common meter is connected to all rooms and each room has its own counter.

In the first case, everything is done as in apartment buildings, and as in the entire power grid - each of the meters connected to the lead-in cable and from it the electrical wiring of the room in which it is necessary to conduct accounting. In the second case, they put a general meter on the input and put their own meter on each of the premises, so you can see the total energy consumption and the consumption of each of consumers (if I can put it this way - sub-consumers), this is sometimes needed to pay for electricity in offices and shopping centers when premises are rented out to different clients.