Check the answer

April 25, 2020   photos  

The 1st one is correct. Input comes in first from the left as a single phase post paid meter. However, others see that both are correct. The first one shows the suppliers side and the second one shows the consumer's side. Both may be correct. In case, the customer has a micro production we can install two energy meters. One for the injected energy of the grid and the other to measure the energy exported to the grid. On the other side, the second one is safer because to protect energy meter too. I saw in some case the energy meter burn due to the internal fault or other reason.