Configuring GSM

1. Goal

• Connect your Charge Charge Controller to your Backend through GSM

2. Requirements

Make sure that

• The Charge Charge Controller of your Charging Station has a GSM module and a corresponding antenna (see Capabilities Table below)
• A SIM card from the Backend vendor or Network operator of choice is present and activated
• A SIM card is inserted in the SIM card slot of your Charge Charge Controller

info

The SIM card must be able to access APN networks and be able to connect to the Internet.

2.1. Does my Charge Controller support GSM?

CC612-1M3PRCC612-1M4PRCC612-2M4PRCC612-2SOPR

CC613-ELM4PRCC613-ELM4PR-M

ICC1324-ConnectICC1324-Connect Plus

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If you can't see the GSM-related configuration options in the Config UI mentioned in this guide, it does not apply to your Charge Controller.

3. Enabling GSM

1. Apply the following configuration:

Location in Config UI	Parameter	Value	Info
NETWORK > GSM	Show Modem Configuration	Show
NETWORK > GSM	Access Point Name (APN)	Refer to your Mobile Network Provider	Access Point Name of the mobile network to be used when establishing connections to the backend system via the built-in modem.
NETWORK > GSM	SIM Card PIN Number	Refer to your Mobile Network Provider	To unlock your SIM card, you must enter the corresponding PIN here. Your network provider will also provide you with the PIN together with the SIM card. If this isn't the case, you should contact your network provider. If the SIM has no active PIN: Leave this field empty. The PIN cannot be managed through the Config UI.
NETWORK > GSM	Network selection mode	Auto (recommended in most cases)	Here you can select whether the GSM modem should automatically (Auto) search for Mobile Network Operators (Network operators) or connect manually. We recommend to generally set the mode to Auto. However, in regions with low network coverage, the GSM module may often jump between networks in Auto mode. In this case, the Manual makes more sense.
NETWORK > GSM	Modem Access Technology	Auto (recommended in most cases)	Choose the cellular generation to use for communication to the Backend. In Auto mode the modem automatically selects the best available standard. We generally recommend auto. This usually ensures a stable connection. However, if you're experiencing stability issues, experiment with different cellular technologies.

1. At the bottom of the Config UI, click , then click to apply the changes

In the Config UI, under DIAGNOSTICS > Connection State (Modem), you can see if the Charge Charge Controller is connected to the Internet.

If you can't see Connection State (Modem)

If you can't see Connection State (Modem), you might have BACKEND > Connection > Connection Type set to something other than GSM. Make sure to set the Connection Type to GSM in order to test the modem connection.

4. Set the Network Operator manually

1. In the Config UI under Network > GSM, set Network selection mode to Manual
2. Under Access Point Name (APN) enter the APN of the Mobile Network Operator

name formats

You must observe the correct format when entering the name. You can also configure this in the Network operator name format field. Alphanumeric short, for example, corresponds to a name with up to 8 characters.

3. Fill in the remaining fields as described in the previous section Enabling GSM

Scanning for networks

If you don't know the correct name with the corresponding format,

1. Scan for available networks by enabling Scan network operators at boot
2. At the bottom of the Config UI, click , then click to apply the changes

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After each restart, the Scan network operators at boot parameter is automatically set to Off.

1. Wait around 1-2 minutes while the Charge Charge Controller scans for networks in the background
2. After waiting, refresh the Legacy Config UI (like you would any other website)
3. In the Legacy Config UI, under State, all available Mobile Network Operators are displayed under Available networks.

All available Mobile Network Operators are displayed in the three different input formats.

Format	Example
Alphanumeric long	Telekom.de
Alphanumeric short	TDG
Numeric	26201

6. Transfer the name of the desired provider into the Requested Network operator field, respecting the required format.

Your network isn't listed?

Get in touch with your Mobile Network Operator if the network isn't showing up even after the recommened waiting period.

With the selection Manual/Auto the Charge Charge Controller first tries to connect manually to the specified Mobile Network Operator. If this fails, the Charge Charge Controller switches to Auto mode.

7. At the bottom of the Config UI, click , then click to apply the changes

5. Avoid roaming charges

tip

Check if you do need to pay for roaming with your network provider

To avoid possible roaming charges, for example at national borders, or in case of unstable network connections, under Network > GSM, set the Mobile Network Operator manually.

6. Troubleshooting

6.1. Config UI access

tip

In general, we recommend using GSM only for Backend connections. Accessing the Config UI remotely is best done by setting up an Ethernet connection.

Q: I can’t reach the Config UI over GSM. Are you blocking ports 80/443 on the Charge Controller?

A: No. We do not block the Config UI port over GSM.

Carriers may block common inbound ports such as 80 (HTTP) and 443 (HTTPS). Contact your GSM provider and clarify whether port 80/443 is blocked for your APN.

Q: Do I need a static public IP on the SIM?

A: Yes if you intend to access the Config UI from the Internet. Ask your Cellular carrier for a plan/APN that provides a static, routable public IP.

Q: HTTP (80) works but HTTPS (443) doesn’t.

A: Cellular carrier restrictions may apply. Refer to your Cellular carrier for details.

Q: How can I isolate Cellular carrier vs Charge Controller issues?

A:

• From the Charge Controller: verify outbound connectivity (ping/curl your OCPP Backend)
• From the Internet: try to connect to the controller’s public IP/port
• If outbound works but inbound doesn’t, it’s a Cellular carrier inbound restriction (static IP / CG‑NAT) problem

Q: What exactly should I ask my Cellular carrier for?

A: Ask for:

• A static, publicly routable IP for your SIM/APN
• Confirmation that inbound ports 80/443 (or your chosen port) are not blocked
• Clarify whether CG‑NAT applies to your APN and how to opt out