EG4 Wi-Fi Dongle Setup: Connect Your Inverter Using EG4 Monitor

Connecting an EG4 Wi-Fi dongle is straightforward once you understand one important update: password-protected dongles require an AP password change before the rest of the setup functions become available. Older dongles do not have that extra step.

The other thing to remember is simple: hardware before software. Get your battery, inverter, solar panels, and AC connections sorted out first. Then you can focus on getting the dongle online instead of chasing hardware errors and Wi-Fi issues at the same time.

I’m using a 12,000XP inverter with a battery system for this walkthrough. The process below uses the EG4 Monitor app, including what to do when the phone reports no internet, the app controls are grayed out, or the old password appears not to work.

What You’ll Learn

  • Complete hardware connections and check DIP switch settings before configuring the dongle.
  • Password-protected dongles require an AP password change before other setup functions become available.
  • Reconnect with the new AP password before entering your home Wi-Fi credentials.
  • Confirm three solid green lights, then bring PV and loads online in stages.

Table of Contents

Before You Start: Finish the Hardware Setup

Before configuring the Wi-Fi dongle, make sure the system’s hardware connections and settings are correct:

  • The battery is properly connected to the inverter.
  • The solar panels are properly connected to the inverter.
  • The inverter is properly connected to the loads panel and applicable AC wiring.
  • The battery DIP switches are set correctly for your installation.
  • The dongle is connected to the inverter.

Incomplete connections or incorrect DIP switch settings can create errors on both the inverter and the monitoring system. Getting those details right first makes the software side much easier.

Connected does not mean everything needs to be powered on

Here’s an important distinction: I want the hardware installation complete, but during dongle configuration, I prefer to have only the battery and inverter powered on. I leave PV input and AC or grid input off while working through this part.

That keeps the initial setup focused on the battery and inverter. Once monitoring is available, I bring on PV, check that it is operating properly, and then turn on the loads and check those. If an error appears, it is easier to connect it to the source or stage that was just enabled.

Follow your equipment’s installation and startup instructions when making connections or switching power sources.

1. Identify Whether Your Dongle Is Password-Protected

There are two dongle versions to account for: password-protected and older, non-password-protected models. A lock symbol on the packaging identifies the password-protected version.

This matters because the protected dongle requires you to change its access point, or AP, password on first use. Until that is done, other connection functions remain disabled.

If your dongle is not password-protected, skip the AP password-change and reconnection steps below. You still need to connect your phone to the dongle and use the app to configure your home Wi-Fi.

2. Connect Your Phone to the Dongle’s Wi-Fi Network

Start in your phone’s settings, not inside the app.

  1. Open Settings and go to Wi-Fi.
  2. Wait for the dongle’s network to appear in the available network list.
  3. Select the network name that matches your dongle’s serial number.
  4. For a new password-protected dongle, enter the default password: 12345678.
  5. Tap Join or your phone’s equivalent connection button.

The example dongle’s serial number is DJ55170662, so that is the network selected for this setup. Use your own dongle’s serial number, not the example.

The same basic starting point applies whether you have an iPhone or an Android phone: open Wi-Fi settings and choose the dongle’s network. If you need help finding those controls on an iPhone, Apple provides a guide to joining a Wi-Fi network.

A no-internet message is expected at this stage

Your phone may report No Internet Connection after joining the dongle. That is okay. The phone is communicating directly with the dongle, and the dongle has not been connected to your internet yet. That is exactly what you are about to configure.

If the phone asks whether to keep using this Wi-Fi network despite the lack of internet, choose the option to stay connected, such as Keep Trying Wi-Fi.

3. Open Dongle Connect in EG4 Monitor

With your phone connected to the dongle, open EG4 Monitor. From the opening screen:

  1. Select Dongle Connect.
  2. Select Wi-Fi Connect.
  3. Allow the connection page to finish loading.

I’m using EG4 Monitor here rather than the Connect app because the Connect app had bugs at the time of this setup.

On a new password-protected dongle, a prompt explains that the AP password must be changed through Dongle Connect Parameters before other functions can be used. Dismiss the prompt to continue.

Most controls will be grayed out at this point. That does not necessarily mean something is wrong. The AP password change is the required next step.

4. Change the Dongle’s AP Password

The AP password is the password your phone uses to join the dongle’s own Wi-Fi network. It is separate from your home Wi-Fi password.

  1. Open Dongle Connect Parameters.
  2. Find the AP Parameter section.
  3. Next to AP Password, tap Set.
  4. When prompted to verify the old password, enter 12345678 for a new dongle whose default password has not been changed.
  5. Tap Next Step.
  6. Enter and save your new AP password.
  7. Wait for the password-update success message.

Keep track of the new password. You will need it immediately to reconnect your phone.

If you get an old AP password mismatch

During my setup, the app initially rejected the default password with an Old AP password mismatch message. The parameters page had not fully populated. After returning to the connection page and reopening the parameters, the AP password field showed a value, and verification worked.

So if you know you entered the correct default password but it keeps failing, check that the app has actually finished loading the dongle’s information. Back out, reopen Dongle Connect Parameters, wait for the fields to populate, and then try verification again.

That was the troubleshooting step that resolved this particular setup. If the mismatch continues, contact support rather than assuming the same fix will apply to every dongle.

5. Reconnect Your Phone Using the New AP Password

Changing the AP password disconnects your phone from the dongle. That is expected, but you need to reconnect before you can send the dongle your home Wi-Fi details.

  1. Return to your phone’s Wi-Fi settings.
  2. Select the dongle’s serial-number network again.
  3. If the phone tries its saved password and reports Incorrect Password, replace it with the new AP password you just saved.
  4. Join the network and remain connected even if the phone reports no internet.

On an iPhone, the dongle may already appear under your saved networks. The old saved password is simply no longer valid.

You may also see a weak-security notice. That is a separate message from the no-internet notice; neither substitutes for checking whether you successfully joined the dongle’s network.

6. Select Your Home Wi-Fi in the App

Return to EG4 Monitor, then open Dongle Connect > Wi-Fi Connect again. Once the page has loaded, the connection controls should be available instead of grayed out.

  1. Open the Home Wi-Fi network selector.
  2. Look for the small gray arrow and a scrollable list of nearby networks.
  3. Select your home Wi-Fi network from that list.
  4. Enter your home Wi-Fi password, not the dongle’s AP password.
  5. Tap Home Wi-Fi Connect.

The network selector is worth paying attention to. For this workflow, you want the scrollable network list, not just a blank field where you can type an SSID manually. SSID is simply the Wi-Fi network name.

If the list has not populated, use the refresh control and check again. In this app, using that control can also switch to manual SSID entry, so make sure you are back in the network-list view before selecting your network.

After submitting the Wi-Fi details, the app should display a setup-success message indicating that the dongle will restart.

7. Confirm Three Solid Green Lights

After the dongle restarts, check its physical indicators. The successful connection state shown in this setup is three solid green lights.

Do not stop at the app’s success message alone. Check the dongle itself to confirm that it has reached the expected state.

If you do not get three solid green lights, revisit the connection process and verify the selected home network and password. The dongle may reconnect automatically after being unplugged and plugged back in, so check its status before assuming you need to start everything over. If further configuration is needed, reconnect your phone to the dongle to access it.

Bring the Rest of the System Online in Stages

Once the dongle connection is established and monitoring is available, return to the staged startup approach:

  1. Confirm the battery and inverter are operating as expected.
  2. Enable PV input and check its operation.
  3. Enable the loads and check their operation.
  4. Review any errors as each part of the system comes online.

The goal is not just to get Wi-Fi connected. It is to make the whole startup easier to understand. Hardware first, one stage at a time, and a physical check of the dongle’s lights at the end.

If you get stuck with the dongle process or need technical help, contact SanTan Solar at 480-584-4281.

Related Articles