Robustel E2C Trinity BACnet Protocol

(Southbound) User Guide

Document Version: V1.1

Gateways & Firmware Requirement:

1. Manual Description

1.1 Manual Purpose

This manual guides technicians to quickly configure the Robustel edge computing gateway to collect data from Southbound BACnet devices (BACnet/IP or BACnet MS/TP). It also covers how to forward the collected data to Northbound systems using MQTT or an OPC UA Server.

1.2 Scope of Application

This manual is written for field implementation engineers and technicians. You do not need deep theoretical knowledge of the BACnet protocol. By following these step-by-step instructions, you can easily connect devices, read data points, and forward data.

2. Basic Concepts & Network Topology

2.1 Gateway Role in the Network

In the BACnet network, the Robustel Gateway acts as the data forwarding machine. Its job is to actively initiate requests, read data from the underlying BACnet devices (such as HVAC controllers, chillers, or smart meters), and then translate this data into IIoT protocols (like MQTT/OPC UA).

2.2 Connection Topology

• BACnet/IP: Devices are connected via standard Ethernet cables. The gateway and the BACnet devices are typically in the same local network subnet. However, if they are not in the same subnet (e.g., cross-network segment via a router), the BBMD (BACnet Broadcast Management Device) protocol can be used to discover and connect the devices.

• BACnet MS/TP: Devices are daisy-chained via an RS485 serial cable. You must connect the "A" and "B" wires correctly and ensure all devices share the same Baud Rate.

3. Preparations

3.1 Hardware Device Requirements

3.2 Environment and Network Requirements

1. The PC and the Gateway must be in the same network segment. (Default Gateway IP: 192.168.0.1)
2. It is highly recommended that you have the Point List (Register Map) provided by the BACnet device manufacturer. This list tells you the specific meanings of the data points. If you do not have it, you can still use the gateway's Auto Search function to discover the points, but you may need the list to interpret the data.

4. Southbound Configuration: BACnet/IP

If your field device uses a network cable (Ethernet), follow this chapter. If it uses an RS485 serial port, skip to Chapter 5.

4.1 Physical Layer: Configuring LAN IP

Purpose of this step: To establish basic network communication. The gateway's LAN IP must be configured so it can successfully "ping" and communicate with the target BACnet/IP device over the Ethernet network.

(Note: If crossing subnets, ensure routers are configured correctly and BBMD is properly handled for device discovery).

1. Log in to the gateway's Web GUI (Default IP: 192.168.0.1, User: admin, Password: admin).
2. Go to Network > LAN.
3. Edit the LAN1 interface and fill in the parameters according to the table below:

1. Click Submit and Save & Apply to apply the network changes.

4.2 Adding a BACnet/IP Device

Purpose of this step: To define the target device in the Data Collection engine so the gateway knows exactly which IP address and port to send data requests to, and how to identify itself on the BACnet network.

First, click Edge Computing in the gateway's Web GUI to enter the E2C Field software. Then follow these steps to add a BACnet IP Device.

Method 1: Manual Configuration

1. Go to Data Collection > Wired Device.
2. Click the + button to add a new device.
3. Configure the following parameters in the popup window:

1. Click Save to create the device profile.

Method 2: Auto Search (Recommended)

If you are unsure of the device's specific parameters, you can use the Auto Search feature to discover BACnet/IP devices on the network.

1. Click the Auto Search button, and select the LAN port.
2. The system will scan the network for available BACnet devices. Select the desired device from the search results and click to add it. This will automatically populate the necessary parameters.

4.3 Adding Data Points

Purpose of this step: To define which specific sensor values or registers (data points) need to be read from the added BACnet device.

Method 1: Auto Search (Highly Recommended) BACnet protocol supports network discovery. This is the fastest way to add points.

1. In the Data Collection list, click on the device name you just created to enter its tag list.
2. Click the Auto Search button at the top.
3. The gateway will automatically query the device and display all available data points (tags).
4. Select the checkboxes next to the points you need and click Save.
5. Check the Latest Value column. If live numbers appear and update periodically, the configuration is fully successful.

Method 2: Manually Add If Auto Search fails or is not supported by the end device, you can add points manually based on the manufacturer's Point List. Click Manually Add and configure:

5. Southbound Configuration: BACnet MS/TP

If your field device uses a 2-wire RS485 serial connection, follow this chapter.

First, click Edge Computing in the gateway's Web GUI to enter the E2C Field software. Then follow these steps to add a BACnet MS/TP Device.

5.1 Physical Layer: Configuring the Serial Port

Purpose of this step: To align the gateway's serial port hardware settings with the field device. In RS485 communications, all devices on the daisy-chain must speak at the exact same speed and format, otherwise, no data can be read.

Warning: Ensure the RS485 wiring is correct (A to A, B to B). If communication fails later, try swapping the A and B wires.

1. Log in to the gateway's Web GUI.
2. Go to Interface > Serial Port, set the Serial Port Type to RS485.

1. Go to Edge Computing > System Settings > Serial Ports.
2. Find the serial port connected to your device (e.g., COM1) and configure:

1. Click Submit to apply the serial settings.

5.2 Adding a BACnet MS/TP Device

Purpose of this step: To tell the Data Collection engine which serial port to listen on and what the MS/TP MAC address (Station ID) of the target device is.

Method 1: Manual Configuration

1. Go to Data Collection > Wired Device.
2. Click the + button to add a new device.
3. Configure the following parameters in the popup window:

1. Click Save to create the device.

Method 2: Auto Search (Recommended)

If you are unsure of the device's specific parameters on the serial network, you can use the Auto Search feature to discover BACnet MS/TP devices.

1. Click the Auto Search button.
2. Configure the following parameters in the popup window:

1. The system will scan the selected serial port for available BACnet devices. Select the desired device from the search results and click to add it. This will automatically populate the necessary parameters like MAC Address.

5.3 Adding Data Points

Purpose of this step: Let the software know which point data to read.

Method 1: Auto Search (Highly Recommended) BACnet protocol supports network discovery. This is the fastest way to add points.

1. In the Data Collection list, click on the device name you just created to enter its tag list.
2. Click the Auto Search button at the top.
3. The gateway will automatically query the device over the RS485 serial network and display all available data points (tags).
4. Select the checkboxes next to the points you need and click Save.

1. Check the Latest Value column. If live numbers appear and update periodically, the configuration is fully successful.

Method 2: Manually Add If Auto Search fails or is not supported by the end device, you must add points manually based on the manufacturer's Point List. Click Manually Add and configure:

6. Device Status and Data Verification

Once the configuration is complete, it is crucial to verify that the gateway is successfully communicating with the field devices and collecting accurate data.

6.1 Checking Device Connection Status

Purpose of this step: To confirm if the gateway has successfully established a connection with the Southbound BACnet device.

1. Go to Edge Computing > Data Collection > Wired Devices.
2. Locate the configured device card in the list.
3. Check the indicator on the top left corner of the device card:
   1. Green: The device connection is normal.
   2. Red: The device connection failed.

6.2 Viewing Data Collection Status and Latest Values

Purpose of this step: To verify that the configured data points are successfully returning valid readings from the field device.

1. Observe the Status, Latest Value, and Update Time columns:
   1. Status: This column shows the collection status of each data point. A green icon indicates the data point is collected normally, while a red icon indicates collection failure.
   2. Latest Value: This column displays the real-time data collected from the field device (e.g., a temperature reading of 25.5 ).

6.3 Modifying Data Values (Write Operation)

Purpose of this step: To send control commands back to the field device (e.g., turning on a relay or setting a new temperature setpoint).

1. Ensure the data point has Read/Write permissions (e.g., Analog Output - AO, or Binary Output - BO). Points with Read Only permission (like AI or BI) cannot be modified.
2. In the tag list, click the Edit icon (usually a pencil symbol) next to the point you want to modify.
3. A Modify Tag Value dialog box will appear. Enter the new desired value and click Save or Confirm.
4. Observe the Latest Value column. It should update to reflect the new value if the write operation was successful.

7. Northbound Configuration: Two Core Scenarios

Once the gateway successfully reads data from Southbound BACnet devices, you can forward this data to the Northbound platform.

7.1 Creating Data Groups (Preparation for Data to Cloud)

Purpose of this step: To organize the collected BACnet data points into logical groups before sending them to the cloud or application systems. Grouping allows you to control exactly which data points are packed and uploaded together in a single payload.

1. Go to the Data to Cloud - Groups tab.
2. Click the + button to add a new group, and set the report type (Period, Change or Change & Period).
3. In the tag selection area, select the BACnet devices and the specific data points (tags) you want to include in this group.
4. Click Save to create the group.

(Note: You will use this created Group in the following MQTT transmission settings to define the upload payload).

7.2 Scenario A: Forwarding to MQTT Broker (Data to Cloud)

This scenario is used to push data to cloud platforms (like AWS, Azure, or private IoT platforms).

1. Go to Data to Cloud, Create Cloud Service, and choose MQTT.
2. Configure the MQTT connection:
   1. Server Address / Port: Enter your cloud server IP and Port (usually 1883).
   2. Client ID: Set a unique ID for the gateway.
   3. Username / Password: Fill in if required by your broker.
3. Go to the Message Management section and add a publish topic.
   1. Topic: Define the topic where data will be published (e.g., gateway/bacnet/data).
   2. Data Group: Select the group you created before.
4. Click Save and ensure the connection status turns to "Connected".
5. Use a MQTT client to check subscribe the message.

7.3 Scenario B: Forwarding to OPC UA Server (Data to SCADA)

This scenario is used to provide data to local factory SCADA or BMS systems. The gateway acts as an OPC UA Server, waiting for the SCADA to connect to it.

1. Go to Data Forwarding.
2. Add a OPC UA Server.
3. Enable the OPCUA Server Configuration and set the Port Number.
4. Set Maximum Connections, and choose Authentication Mode (Anonymous or User)。If User Mode is selected, you need to set a username and a password.
5. Submit and Publish.
6. In your SCADA software, use the URL opc.tcp://[Gateway_LAN_IP]:4840 to discover the gateway and browse the BACnet data points.

8. Troubleshooting / FAQ

9. Core Parameter Quick Reference

For quick on-site configuration, refer to these industry-standard default values. Unless explicitly required by the site, do not change them: