Why does one phase import electricity while another exports it?

What you will see

• One phase shows export while another shows import.
• Total solar generation looks sufficient, but some phase readings still show grid use.
• App import and export totals differ from another meter’s figures.
• The behaviour changes when a large single-phase appliance runs.

Why it happens

Demand and generation can differ by phase. A phase with more local supply than demand can export while another needs electricity from the grid. Solis documents this simultaneous behaviour and explains that monitoring systems can aggregate phase flows differently.

Local supply exceeds the load: export.

Load exceeds local supply: import.

Supply and load are closely matched: little net flow.

Whether the inverter can adjust output independently by phase depends on its model and operating arrangement. Supported Solis systems, for example, distinguish balanced output from a permitted unbalanced control function.

Incorrect phase association or current-transformer orientation can also produce misleading readings or poor control. That possibility requires installer verification; customers should not move sensors to make arrows look correct.

Do not infer electricity charges from a single power-flow screen. A technical comparison should identify which meter, register, time period and aggregation method each figure represents before any billing conclusion is drawn.

Diagram

Each phase has its own balance

L1: export

Local supply exceeds the load.

L2: import

Load exceeds local supply.

L3: little flow

Supply and load closely matched.

Wrong phase association or sensor orientation can also produce misleading readings. That needs installer verification.

What you can check yourself

• Save all three phase readings together with total load and solar power.
• Note the appliances operating at that time, especially larger single-phase loads.
• Record the inverter and monitoring-meter model names from existing documents.
• Check whether the behaviour began after metering, wiring or inverter changes.
• If comparing energy totals, use the same start and end times and retain the original screenshots.

What not to do

• Do not reverse current transformers, change phase assignments or enable an unfamiliar control option yourself.
• Do not assume every meter uses the same plus/minus sign convention.

When to call us

• Request a review if the readings conflict with known operation, unexpected imports persist, or the behaviour changed after electrical work. The installer should verify measurement first, then assess the control arrangement and load distribution.

Three-phase metering in Faisalabad and Lahore

How FESCO and LESCO meters total the phases decides what appears on your bill. Our team verifies measurement first, then the control arrangement.

Send us

The inverter and meter models, simultaneous phase readings, appliance activity, relevant energy totals, and your city and area.