Solar app figures don’t add up

If the app shows offline or a flat zero, read solar app offline or showing zero instead. This page is for an app that is online but showing numbers you do not believe.

Solar app showing wrong data: where the numbers come from

A monitoring app gets its numbers from up to three places:

1. The inverter itself, which measures solar (PV) power, its AC output and, on hybrids, battery charge and discharge.
2. A CT clamp or smart meter at your grid connection, which measures import and export. House consumption is usually calculated from this and the inverter's output.
3. The cloud platform, which adds up the readings, applies your time zone, plant capacity and tariff, and draws the graphs.

An error at any of these points shows up as "wrong data". Solar generation figures come mostly from the inverter. Consumption, import and export figures depend on the CT or meter. "Savings" and percentages depend on settings typed into the app. Our monitoring app guide explains which app goes with which brand.

Quick-check table

Safe owner checks

All of these are done on your phone, the inverter screen and the DISCO meter's display. Do not open the inverter or the distribution board, and do not change installer-level settings.

1. Compare the inverter screen with the app. Note the live power and today's total on both at the same moment. Small delays are normal; many platforms update every few minutes, not in real time.
2. Check the date and time. If the inverter or plant time zone is wrong, "today" can start and end at the wrong hour, and daily yields shift between days. Note what the inverter screen shows.
3. Check plant settings. In the app's plant or site settings, check the installed capacity (kWp), time zone and tariff. Wrong capacity distorts "kWh per kWp" and performance figures. Wrong tariff distorts savings figures, which are only ever estimates anyway.
4. Do an evening sign check. After sunset, with lights and fans on, the app should show the house importing from the grid and consumption as a positive number. If it shows negative consumption or export at night, the CT or sign is wrong.
5. Do a midday load test. Switch a large load, such as an electric kettle, on and off and watch consumption rise and fall by roughly the same amount.
6. Compare a week of meter readings. Write down the DISCO meter's import and export registers at the same time each day for a week. Compare the daily differences with the app. Our guide to reading your electricity bill shows where these numbers appear.
7. Look for gaps. Missing hours after load-shedding or a router outage are a data problem; the inverter keeps its own lifetime total. Whether the dongle fills the gap later depends on the model.
8. Screenshot everything. The power-flow page, the daily graph, the plant settings and the inverter screen.

Why the numbers can differ even when nothing is broken

• Different measuring points. The inverter measures its own output; the DISCO meter measures your whole connection. They will never match exactly.
• Different definitions. On a hybrid, "yield" may mean PV production or the inverter's AC output, which includes battery discharge. Brands label this differently.
• Self-consumption and losses. The inverter and battery use a little power themselves, and conversion is never 100% efficient.
• Rounding and delay. Apps sum readings taken every few minutes, so short spikes can be missed.

A difference of a few percent between the app and the meter over a month is usually not a fault. A consistent large gap, or numbers with the wrong sign, is.

What an engineer will check

• CT direction, position and phase. Solis's guidance, for example, uses a sign convention where import and export carry opposite signs, and tests polarity by creating a pure import condition: every phase should read as import. A phase that reads the other way has a reversed CT. Other brands follow similar logic with their own conventions.
• Meter type and communication settings, so the inverter reads the meter it expects.
• Device list in the app, to remove a duplicate inverter or add a missing one.
• Dongle and firmware, and re-binding the dongle to the plant if it was replaced. See inverter Wi-Fi setup.
• Battery SOC calibration on hybrid systems.

If a reversed CT is also controlling export limiting, the same fault can make the system export when it should not; see zero export not working.

How to prevent wrong data

• At handover, ask for the app to be checked against the inverter screen and a simple load test.
• Make sure the plant is under your own account, with your installer kept as a viewer for support.
• Keep the plant's kWp, tariff and time zone correct after any expansion.
• Note dates of firmware updates, dongle changes and rewiring. Most sudden changes in the data line up with one of them.
• Judge real performance from clear-day production and longer periods, not one odd day. Our year one review guide shows how, and low solar production covers real output problems. For room-by-room detail, see home energy monitoring.

For Solar Works customers

If we installed your system, WhatsApp 0336 666 4321 with the inverter model, a photo of the inverter screen and screenshots of the app's power-flow page and settings. Many app problems can be sorted by checking settings remotely, where the equipment allows. Our 1-year service warranty applies under the applicable project terms, and after-sales complaints are handled by our own engineering staff. See how after-sales service works and our Solis inverters page.

We can also review monitoring set-up on systems installed by other companies, as a chargeable service in Punjab.

Frequently asked questions

Why is my solar app showing wrong data?

Usually because of a setting or sensor: wrong time zone, wrong plant capacity, a missing or reversed CT, or missing data after an outage. Compare the app with the inverter screen first to see where the error starts.

Why is my inverter today yield wrong?

Check the date and time on the inverter and the app's time zone. If either is wrong, the daily total resets at the wrong hour. A data gap after an outage can also make today's total look low in the app while the inverter's own total is correct.

Why is consumption shown negative in my solar app?

Negative consumption usually means the CT sensor is facing the wrong way or the sign setting is reversed, so the app treats import as export. An installer can correct the CT or setting and test it.

Monitoring app wrong production: why doesn't it match my inverter?

The app may be delayed, missing hours after an outage, or counting a device twice. Compare the lifetime totals on the inverter screen and in the app. If the gap keeps growing, ask your installer to check the dongle and device list.

Should the app match my electricity bill exactly?

No. The app and the DISCO meter measure at different points and over different periods. Small differences are normal. Large, consistent differences are worth checking.

Why does my app show zero consumption?

The app needs a CT clamp or meter at the grid connection to measure house consumption. If none was fitted, or it is disconnected or not configured, consumption can show zero while solar production looks fine.

Sources

1. Solis, "Smart meter phase rotation and CT polarity verification"
2. Solis, "CT detection function on the SolisCloud app"