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.
Each conductor wire has a resistance. Resistance means heat development inside the wire. Technically it’s a loss.
Usually the power supply systems are named with single phase, three-phase three wire or three-phase four-wire. The German VDE and the IEC60364-1 have unified the supply systems based on grounding.
An energy meter has certain specifications, including maximum current. This is the base for all kind of meter type tests.
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.
The IEC 62052-11 Edition 2 has introduced some changes for the meter marking and documentation. Today we cover the mandatory content of the nameplate for IEC meters.