Difference Between ID1 and ID2 Meters

Difference Between ID1 and ID2 Meters

Overview

Meters can be assigned an ID number between 1 and 8, defining their role within the system.

The ID1 meter is always the main grid meter, while ID2–ID8 are used for monitoring additional devices.

Meter Roles

ID

Function

Typical Use Case

ID1

Main grid import/export meter

Monitors total property energy flow

ID2

Secondary generation or device meter

Tracks external PV generation

ID3–ID8

Reserved for future integrations

Potential for EVs, heat pumps, etc.


Example Setup

  • ID1 (Grid): Measures total property load and grid import/export.

  • ID2 (PV String): Measures an external PV system’s generation before the inverter.

    The inverter uses both meters to optimise battery charge/discharge and overall energy balance.

Notes

  • Only ID1 communicates directly with the inverter.

  • ID2 meters are bridged to the same voltage reference as ID1 for accurate phase correlation.

  • ID2 CTs must clamp the PV inverter’s live feed, arrow pointing toward property load.


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