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How do you handle split CTs, three-phase or multiple meter tails for battery and export control?

Short answer

Every path between the grid and the house must be measured. With split tails, Economy 7 double tails or several meters feeding one installation, use a CT per path or relocate the measurement point; on three-phase use a CT per phase and a controller that supports phase balancing or net metering. Unmeasured paths corrupt limitation and battery logic.

Last checked 24 September 2026 · 1 source

In more detail

  • Confirm whether the DNO export limit is per phase or total (G99 SGI limits are per phase).
  • Use manufacturer-approved CT extensions or meter-based (Modbus) measurement for long runs.
  • Document CT locations in the schematic for G98/G99 Form B/A3 and future service.

The facts, dated

  1. 01
    G99 SGI-2 export limit is expressed per phase — 16 A per phase

    standard · GB · checked 24 September 2026 · dcode.org.uk

Sources

Last checked: 24 September 2026