Nexto Xpress - How to Use 3G/4G

This tutorial describes guidelines and procedures for using the USB port with a 3G/4G modem on the Nexto Xpress.

Components

Software: MasterTool IEC XE 3.30

PLC: XP300 with XP910 accessory (3G/4G modem Huawei E3276)

Tutorial Sections

1. ARCHITECTURE

2. DEVELOPMENT

2.1. Configuring the IP Address on the PLC

2.2. Configuring the 3G/4G Modem

2.3. Connecting to the PLC with Mastertool

1. ARCHITECTURE

In the architecture of this tutorial, the Ethernet port of the XP300 was connected to the Ethernet port of the computer through the NX9202 cable, and the 3G/4G modem Huawei E3276 was connected to the USB port of the XP300.

2. DEVELOPMENT

This tutorial will show the steps to access the Nexto Xpress Series PLCs via 3G/4G modem (USB). This USB modem with SIM chip can be used to connect the PLC to the Internet using the cellular data network (telephone services, such as sending SMS, are not implemented). It also allows the use of Nexto Xpress controllers to implement telemetry and IoT applications. There are basically two types of modems: bridge and router. In this tutorial, we will use the bridge type.

For bridge devices, once it is correctly detected and the SIM parameters are configured, the controller starts a background process that continuously controls the modem to keep it connected to the Internet, so there is no need for manual intervention. Therefore, if the connection is interrupted for any reason, the controller will attempt to reconnect automatically.

It is important to have the Nexto Xpress Series Manual on hand, allowing you to consult it during the application steps. This document will guide you on technical characteristics, installation, programming, and configurations.

2.1. Configuring the IP Address on the PLC

Click on NET 1 in your device tree.

Enter an IP address for your PLC in the project settings.

Note: It is possible to change your PLC's IP address using Easy Connection if necessary. Remember that when changing your PLC's IP, it may be necessary to set your computer to the same IP range as the PLC in order to regain access to it.

2.2. Configuring the 3G/4G Modem

Enter your PLC's IP into your computer's browser and on its page go to the Controller Management tab. In this tab, on the left side, select the USB Devices menu option.

If username and password are required, simply enter admin, admin respectively.

Connect the 3G/4G modem to the USB port of your PLC.

After the modem device is detected and mounted correctly, the USB LED will light up and the device information should be displayed on your screen:

The Status section is where all diagnostics related to the USB modem are displayed:

• Configuration status (which does not depend on the device status)

• Internet connection status

• Modem IP address.

These fields are updated automatically whenever a value is updated (it is not necessary to manually reload the page). The same information is also provided in the symbolic variables diagnostic structure, which also contains a detailed description of possible values for each field.

The Configuration section is where the user performs the modem configuration. For bridge modems, this section is used to enter the SIM chip information.

This section contains the following buttons:

Import: loads the configuration from an external file

Export: saves the current configuration to an external file

Reset: erases the modem configuration from the controller's memory

Apply: writes the configuration to the controller's memory

Click Apply and the modem's IP address should be displayed.

The configuration field should show the status as Configured and the connection field should show the status as Connected.

Note: If the USB modem is configured, the controller system will set it as the default gateway for all Ethernet communication. NET1 returns as the default gateway when the USB modem has been removed.

2.3. Connecting to the PLC with Mastertool

With the modem's IP address configured, we can remotely access the controller system's web page to view status and diagnostics (firmware update is not supported). To do this, just enter the modem's IP address in your browser.

After completing the previous configurations, remove the Ethernet cable from your PLC. In Mastertool, go to the device tree and double-click on Device.

Click on Communication Settings and then on Add Gateway...

The Gateway window will open. In IP-Adress, enter the modem IP configured earlier.

In the created gateway, double-click. The PLC in use, in this case the XP340, will appear with its IP and the status of Active. The PLC will be ready to receive the project developed in Mastertool IEC XE.

Note: When accessing the controller remotely, it is necessary to know the modem's IP address on the internet. However, the IP is dynamic and will change with each connection process. One way to solve this problem is to publish the IP address (available in the modem's diagnostic variables) via MQTT.