How to Connect an Alfen Charger

Alfen chargers require a TLS root certificate to be uploaded before they can establish a secure WebSocket (WSS) connection to the eMabler platform. This is done using Alfen's ACE Service Installer app. Without this step, the charger will fail to connect with the error: "try to establish tls, missing server root cert".

This guide walks you through the full process of connecting an Alfen charger to eMabler.

Prerequisites

Before you begin, make sure you have:

• ACE Service Installer app installed on your mobile device or laptop (available from Alfen)

• Bluetooth or Wi-Fi access to the Alfen charger

• eMabler's TLS root certificate file (see Step 1 below for how to obtain it)

• The charger registered in the eMabler platform (see: Connecting a Charger to a Site)

• The OCPP Charger ID you plan to use for this charger

Step 1: Obtain the eMabler TLS Root Certificate

The TLS root certificate can be fetched directly from the eMabler OCPP endpoint using openssl. Run the following command on your computer:

For production:

openssl s_client -connect ocpp.emabler.io:443 -showcerts </dev/null 2>/dev/null | awk '/BEGIN CERTIFICATE/,/END CERTIFICATE/{ if (cert) print; if (/BEGIN/) cert=1 } /END CERTIFICATE/{ cert=0 }' > emabler-root-ca.pem

For test environment:

openssl s_client -connect ocpp.emabler.net:443 -showcerts </dev/null 2>/dev/null | awk '/BEGIN CERTIFICATE/,/END CERTIFICATE/{ if (cert) print; if (/BEGIN/) cert=1 } /END CERTIFICATE/{ cert=0 }' > emabler-root-ca.pem

This extracts the root CA certificate (the last certificate in the chain) and saves it to emabler-root-ca.pem.

Tip: You can verify the certificate was fetched correctly by running:

BASH

openssl x509 -in emabler-root-ca.pem -text -noout

If you are unable to run openssl, you can also request the certificate file from eMabler Support.

Step 2: Connect to the Charger via ACE Service Installer

1. Open the ACE Service Installer app.

2. Connect to the Alfen charger via Bluetooth (or Wi-Fi, depending on model).

3. Log in with the appropriate installer credentials.

Step 3: Upload the TLS Root Certificate

This is the critical step that differentiates Alfen from most other charger brands. Alfen chargers do not trust external OCPP backends by default — you must explicitly upload the server's root certificate.

1. In the ACE Service Installer, navigate to the Certificates or Security section.

2. Select Upload Certificate (or "Install Root Certificate").

3. Choose the emabler-root-ca.pem file you obtained in Step 1.

4. Confirm the upload and wait for the charger to process the certificate.

Note: On some older firmware versions, the certificate may need to be uploaded as a firmware file. The ACE app will guide you through this process.

Step 4: Configure the OCPP Connection

Once the certificate is installed, configure the OCPP backend URL:

1. In the ACE Service Installer, navigate to the OCPP or Back Office settings.

2. Set the OCPP backend URL based on your environment:

3. Set the Charger Identity / CPO Name to the OCPP Charger ID that matches the ID registered in the eMabler platform.

4. Set the Security Profile to 0 or as instructed by eMabler.

5. Save the configuration.

Step 5: Verify the Connection

1. After saving, the charger will attempt to connect to eMabler.

2. In eMabler Connect, navigate to the charger and verify that the status changes to Online.

3. If the charger does not come online within a few minutes, check the following:

   • The charger has an active internet connection (Ethernet or 4G).

   • The OCPP URL is correct and includes the trailing /.

   • The Charger ID in eMabler matches exactly what is configured on the charger.

   • The TLS certificate was uploaded successfully.

Troubleshooting

Need Help?

If you need assistance with the setup, contact eMabler Support.