Fox ESS Fox Cloud offline — WiFi dongle reconnection
H1 inverter dropped off Fox Cloud? The WiFi dongle has almost certainly lost its connection to your home network — usually after a router change, password update, or ISP equipment swap. This guide walks through checking the dongle LED, reconnecting via AP mode, and fixing weak signal issues.
Tell us what the WiFi dongle LED is doing and whether your router has recently changed. We reconnect Fox ESS monitoring remotely in a single session.
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⚡ Safety Warning
Do not open your inverter or interfere with DC cabling. Solar panels produce live DC voltage whenever exposed to light. Always use your DC isolator switch and contact a qualified solar engineer for hands-on fault diagnosis.
Step-by-step Fox Cloud reconnection
Work through these steps in order. Most Fox Cloud offline issues are resolved by step 3 or 4 — the router has changed and the dongle needs reconnecting.
Before troubleshooting your own system, check whether the Fox Cloud platform is experiencing an outage. Try logging in at foxesscloud.com from a desktop browser. If the portal loads but shows your inverter offline, the issue is local to your system. If the portal itself is down or very slow, the problem is server-side and will resolve without any action on your part.
Look at the WiFi dongle plugged into the bottom or side of your H1 inverter. Slow flash (once every two seconds) means the dongle is connected to your router and communicating normally — the issue may be a temporary Fox Cloud delay. Rapid flash or solid red means the dongle has lost its WiFi connection and needs reconnecting. No light at all means the dongle has no power — check it is fully seated in the port and the collar is tight.
The most common reason for Fox Cloud going offline is a change to the home network. This includes a new router from your ISP, a changed WiFi password, a firmware update that reset the network name, or a switch from 2.4GHz to 5GHz only. The Fox ESS WiFi dongle only supports 2.4GHz networks. If your router is broadcasting 5GHz only, the dongle cannot connect. Check your router settings and ensure a 2.4GHz network is available.
On your phone, go to WiFi settings and connect to the dongle's access point — the SSID is W-XXXXXXX (where X is the dongle serial number) and the password is mtmt2020. Your phone may warn there is no internet — connect anyway. Open a browser and go to 192.168.1.1. If asked for a login password, enter 12345678. Select your home WiFi network from the dropdown, enter the password, and press Save. The dongle will reboot and the LED should begin flashing slowly within a few minutes.
If the dongle's access point (W-XXXXXXX) does not appear in your phone's WiFi list, power cycle it. Unscrew the collar at the top of the dongle, pull it downwards to remove it from the inverter port, wait 30 seconds, then plug it back in firmly and retighten the collar. The dongle should now broadcast its access point for reconnection. If it still does not appear after power cycling, the dongle itself may have a hardware fault.
If the dongle connects but drops offline repeatedly, the WiFi signal at the inverter location is likely too weak. Most inverters are in garages, lofts, or utility rooms with poor WiFi coverage. A 2.4GHz WiFi range extender placed between the router and the inverter will usually fix recurring dropouts. A powerline adapter with WiFi is another option if the inverter is far from the router. If the dongle still disconnects after improving signal strength, contact STS for a remote diagnostic.
Fox Cloud offline — what you need to know
Fox Cloud is the monitoring platform for all Fox ESS inverter and battery systems. It relies on a small WiFi dongle plugged into the inverter to send generation, consumption, and battery data to the cloud. When that dongle loses its WiFi connection, the inverter keeps working normally but stops reporting data — the app shows the system as offline even though it is still generating and exporting. No data is lost permanently; once the connection is restored, historical data backfills automatically.
The dongle only supports 2.4GHz WiFi, which is the single most important thing to check. Many modern routers default to 5GHz or use band steering that can deprioritise 2.4GHz devices. After a router change or ISP equipment upgrade, the dongle needs to be manually reconnected via its built-in access point (AP mode). STS can walk you through this process remotely, or diagnose deeper connectivity issues using Fox Cloud installer-level access if the standard reconnection steps do not resolve the problem. We are independent from Fox ESS and from your original installer.
Fox Cloud connectivity — common questions
The most common cause is the WiFi dongle losing its connection to your home network. This usually happens after a router change, a WiFi password update, or an ISP equipment upgrade. Check the LED on the WiFi dongle — a rapid flash or no light means it is disconnected. You will need to reconnect it via the dongle's built-in access point at 192.168.1.1.
Connect your phone to the dongle's WiFi access point (SSID: W-XXXXXXX, password: mtmt2020). Open a browser and go to 192.168.1.1 — if prompted for a password, enter 12345678. Select your new home WiFi network from the dropdown, enter the password, and press Save. The dongle will reboot and should reconnect to Fox Cloud within a few minutes. If you're unsure, book a remote diagnostic and we'll walk you through it.
A slow flash (once every two seconds) means the dongle is connected to WiFi and communicating with Fox Cloud normally. A rapid flash or solid red light means the dongle has lost its WiFi connection and needs to be reconnected via AP mode. No light at all means the dongle has no power — check it is fully seated in the inverter port and the collar is tightened securely.
No. The Fox ESS WiFi dongle only supports 2.4GHz networks. If your router is set to 5GHz only, or the 2.4GHz band has been disabled, the dongle will not connect. Most dual-band routers broadcast both frequencies by default, but some ISP router updates can disable 2.4GHz. Check your router settings and ensure a 2.4GHz network is available and broadcasting.
Intermittent disconnections are almost always caused by weak WiFi signal at the inverter location. Inverters are typically in garages, lofts, or utility rooms with poor coverage. A 2.4GHz WiFi range extender or powerline adapter placed between the router and inverter will usually fix recurring dropouts. Also check that your router is not set to change WiFi channels automatically, as channel hopping can cause brief disconnections.
Fox Cloud still offline?
Tell us what the WiFi dongle LED is doing, whether your router has changed, and what you see in the Fox Cloud app. We diagnose Fox ESS connectivity issues remotely using installer-level portal access. Independent from Fox ESS and your installer.