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Problem diagnosis · AlphaESS

AlphaESS AlphaCloud Offline — WiFi Dongle, 4G Module & Portal Reconnection

AlphaCloud shows no data, the app says your system is offline, and you have no idea if your SMILE inverter is even working. The good news: it almost certainly is. The communication dongle has lost its internet connection — your solar generation, battery storage, and grid export all continue normally in the background.

WiFi & 4G dongle diagnostics AlphaCloud portal restoration All SMILE models supported
AlphaCloud not showing any data?

Most AlphaESS portal connectivity issues are resolved remotely in a single session. We reconfigure the dongle and restore your AlphaCloud access.

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Key point: AlphaCloud going offline does not mean your solar system has stopped working. The SMILE inverter and SMILE B battery continue operating normally — you just can't see the data remotely until the communication dongle is reconnected.

Diagnostics

5-step AlphaCloud reconnection diagnosis

When AlphaCloud goes offline, the problem is in the communication link between the SMILE inverter and the cloud portal. The dongle has lost internet connectivity. Work through these steps in order.

1

Check the communication dongle LED on the SMILE inverter

The communication dongle plugs into the bottom or side of the SMILE inverter. Locate it and check the LED:

Dongle LED status
Solid green/blue: Connected and transmitting data to AlphaCloud — if portal is still empty, the issue is server-side
Flashing: Attempting to connect — normal during startup, but should not persist beyond a few minutes
Off: No power — dongle is loose in its port, or the dongle hardware has failed

If the LED is off, reseat the dongle firmly in the communication port. A loose dongle is the simplest and most common cause of AlphaCloud going offline.

2

Verify WiFi connectivity to your router

The WiFi dongle requires a 2.4GHz WiFi connection. Common reasons for lost connectivity:

Router replaced: New router means new WiFi password — the dongle still has the old credentials stored
Password changed: Any WiFi password update requires the dongle to be reconfigured
5GHz only: Many modern routers default to 5GHz or use band steering — the AlphaESS dongle cannot see 5GHz networks
Router firmware update: BT, Virgin, and Sky hub updates sometimes reset WiFi settings or enable band steering

Check that your router is broadcasting a 2.4GHz network and that the password matches what is stored in the dongle.

3

Power-cycle the SMILE inverter to reset the communication module

A power cycle clears transient connection failures and cached states:

• Turn off the inverter at the AC isolator
• Wait 30 seconds for internal capacitors to discharge
• Turn the AC isolator back on
• The communication dongle reinitialises on startup and attempts to reconnect to AlphaCloud

This resolves most firmware-induced communication hangs. Data should appear in AlphaCloud within a few minutes of the inverter coming back online.

Note: power cycling the inverter does not lose your working mode settings, charge schedules, or any other configuration.

4

Check the 4G module signal if using cellular connectivity

Some AlphaESS installations use a 4G module instead of WiFi — typically where the inverter is in a garage, basement, or metal enclosure with poor WiFi coverage:

Flashing but not solid: The module has power but cannot establish a data connection — likely a signal issue
SIM deactivated: Some 4G modules use pre-paid SIMs that expire if not topped up or renewed
Poor signal: Metal inverter enclosures and concrete basements severely attenuate cellular signal — an external antenna may be needed
Network outage: Check whether other devices on the same mobile network are working

If the SIM is active but signal is weak, relocating the 4G module or adding an external antenna resolves the issue.

5

Reconfigure the dongle via the AlphaESS app

If power cycling did not restore connectivity, the dongle needs to be reconfigured with your current network credentials:

• Open the AlphaESS mobile app and go to device settings
• Select the communication module and re-enter the WiFi SSID and password
• For 4G modules, verify the APN settings match your SIM provider
• The dongle restarts and attempts to connect after saving

The app communicates with the dongle via Bluetooth — ensure Bluetooth is enabled on your phone and you are within 2 metres of the inverter. If the app cannot find the dongle, the dongle itself may have failed and need replacing.

If you are not comfortable reconfiguring the dongle, we can talk you through the process remotely or arrange an engineer visit.

About AlphaCloud monitoring on AlphaESS systems

AlphaCloud is AlphaESS's cloud monitoring platform. It provides real-time and historical data for solar generation, battery state of charge, grid import/export, and working mode status. The SMILE inverter sends this data via a communication dongle — either a WiFi stick that connects to your home router, or a 4G cellular module with its own SIM card. Both plug into the inverter's communication port.

The most common triggers for AlphaCloud going offline are router changes (new router means new WiFi credentials), ISP firmware updates (BT, Virgin, and Sky hubs sometimes reset WiFi settings), and loose dongles (the dongle gradually works loose from vibration or temperature cycling). Less common but still seen: 4G SIM expiry, communication dongle hardware failure, and AlphaESS server maintenance. In all cases, the solar system itself continues working — the outage is monitoring-only.

FAQs

AlphaCloud connectivity — common questions

AlphaCloud goes offline when the communication dongle on the SMILE inverter loses its internet connection. Common causes: loose dongle, WiFi password change, router replacement, or deactivated 4G SIM. Your solar system continues working normally — only remote monitoring is affected. A power cycle usually restores the connection.

Open the AlphaESS app, go to device settings, select the WiFi module, and re-enter your new network name and password. The dongle needs 2.4GHz WiFi — it cannot connect to 5GHz networks. After saving, the dongle restarts and data should appear in AlphaCloud within a few minutes.

Solid green or blue means connected and transmitting. Flashing means attempting to connect — normal briefly at startup but should not persist. LED off means no power — the dongle may be loose or have failed. Reseat it firmly before assuming a hardware fault.

Yes. AlphaCloud is monitoring and remote management only. When the dongle loses its connection, you lose real-time data and remote working mode changes — but the SMILE inverter and battery continue operating normally. Generation, charging, and export all continue according to the last configured settings.

Most connectivity issues are resolved remotely. Our remote diagnostic starts from £75 and covers the full communication audit — dongle status, WiFi or 4G configuration, app reconfiguration, and portal verification. If the dongle needs replacing, we provide the exact part reference and can arrange supply.

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AlphaCloud offline and can't fix it?

Tell us what the dongle LED is showing and what you've tried. We'll diagnose the communication fault and restore your AlphaCloud access — usually same day.

Remote diagnosis from £75
WiFi and 4G dongle configuration
Replacement dongle supply if needed

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