The phase to neutral supply voltage is controlled by the power generation companies and utilities by using transformers with on-load tap changers. Depending on the region you can find different supply voltages.
Electronic meters with build-in relays can serve for various functionalities. By IEC62052-11 Ed.2 the name for this sort of relays is Supply Control Switch (SCS).
Electronic energy meters, especially those with STS payment functions have the ability to give an alarm. Low credit is a typical example.
Electronic energy meters with a build-in load switch can be programmed for a maximum load. If a consumer exceeds the limit, he will be disconnected
Voltage instrument transformers (VT, sometimes also abbreviated with PT) are used on the primary side of medium- and high voltage distribution transformers.
Transformer operated energy meters need instrument transformers to reduce high voltage- and current values to lower quantities for measurement purpose.
If you are using STS prepayment energy meters you might remember that updates are required for the key management centre (KMC), the security modules and the vending software.
Will an electronic energy meter measure accurate when I invert phase and neutral during installation? This question came up recently.
The IEC 62052-11 Ed.2 comes with a lot of changes for meter type testing. Another new introduced test for electromagnetic compatibility (EMC) is the ring wave immunity test.
A sudden shutdown of 150,000 smart meters happened recently in the Uttar Pradesh province, India.