FAQs - Energy Metering

Energy meters often feature communication protocols for remote monitoring and integration into energy management systems. Common protocols include:

Modbus (RS485, TCP/IP) which is widely used for industrial automation and monitoring due to reliability and simplicity.

M-Bus which is a common in utility metering for water, gas, and electricity application.

Ethernet/IP which is used for high-speed data transmission in networked environments.

Wireless (based on LoRa, Zigbee, Wi-Fi, GSM/4G/5G) which enables remote monitoring in smart metering applications.

Selecting the right protocol depends on the application, system integration needs, and data transmission requirements.

Current transformers (CTs) reduce high electrical currents to a manageable level for energy meters. They are essential for measuring large loads safely and accurately. CTs are classified by their ratio (e.g., 100:5A), which determines the output current relative to the primary current.

Current Transformers must be installed correctly based on orientation, burden matching and secondary circuit considerations. Orientation refers to correct polarity (P1 facing the source) ensures accurate readings. Burden Matching refers to the CT’s burden (VA rating) which should match the meter’s requirements to avoid measurement errors. Secondary Circuit Considerations refers to the secondary side which should never be left open to prevent high voltage buildup.

Energy meters should only be installed by suitably qualified engineers, elecricians and elecrical contractors.To install an energy meter correctly, it is important to firstly choose the right meter (single-phase or three-phase meter depending on the power system, sizing in Amps and measurements required). The chosen meter can then be installed using the correct wiring in terms of connectin voltage and current inputs, made according to the relevant wiring diagram. How the meter is mounted and installed will also depend on its format (DIN rail, panel mount, wall mount, pole mount etc). The meter will also require protection from energy surges and short-circuits and must be installed with appropriately sized circuit breakers or fuses to prevent damage. Once installed the installation cannot be certified and signed off without verification and testing to ensure the installation is electrically safe and provided readings and accuracy required.