Leveraging existing BMS with akenza

The Building Management System (BMS) is a silent orchestrator of efficiency within the architecture of modern buildings. Operating on three hierarchical levels, the BMS combines sensors, actors, controllers, and management interfaces to optimize building performance. 

A typical Building Management System consists of three levels:

Field level: This tier encompasses sensors such as temperature and air quality and actuators like light switches, blinds, and ventilation flaps. Common field buses include KNX, BACnet, and Modbus. 

Automation level: Controllers and I/O modules reside here, executing logic for controllers such as for temperature and HVAC. It is characterized by the German concept of ‘MSR = Messen Steuern Regeln’ or ‘MCR - Metering Control and Regulation technologies’ in English. 

Management level: This is the interface for facility management and operators, often presented as a web interface for accessing building data and functions. It sends commands to the field level based on values entered by the user. 

Imagine a building equipped with energy meters, flaps, occupancy monitors, room thermostats, and pressure sensors. These all enrich the BMS with measurement data, fault messages, set values, and general equipment states. A single command on the management level can trigger commands to adjust HVAC settings and lighting levels or machinery operation modes. This is one example demonstrating the power of BMS to optimize building performance. 

BMS architecture diagram

Understanding the BMS architecture: wired systems, LoRaWAN technology, and cellular gateways

Depending on the age of the building, the sensors and actuators will either be connected to the building controller by cables, a LoRaWAN (Long Range Wide Area Network) infrastructure, or cellular gateways. 

Wired sensors

Wired sensors, as the name suggests, rely on physical cables for communication. These sensors are typically hardwired into the building’s infrastructure and connected to a central control system. They can communicate over wired cables such as KNX, BACnet, M-Bus, and many other fieldbus protocols. 

One of the primary advantages of wired sensors is their reliability and the initial infrastructure investment already made. Since they are directly connected to the control system, they offer real-time data with minimal latency. Additionally, wired sensors often have a lower risk of interference compared to wireless alternatives. 

However, installing wired sensors can be labor-intensive and costly, especially in retrofitting existing buildings where running new cables may be challenging. Additionally, the inflexibility of cable installations can limit the scalability of the BMS. 

LoRaWAN sensors

LoRaWAN sensors, on the other hand, are wireless sensors that operate using the LoRaWAN protocol. LoRaWAN is a low-power, wide-area networking technology designed for long-range communication with low data rates, making it ideal for IoT applications in buildings. 

LoRaWAN sensors are battery-powered and communicate wirelessly with a LoRaWAN gateway, which then forwards the data to a central server or cloud platform. 

Selection of LoRaWAN devices we support in our Device Type Library

One of the key advantages of LoRaWAN sensors is their scalability. Since they are wireless, they can be easily installed and deployed without the need for cabling. This makes them particularly well-suited for retrofitting existing buildings or adding new sensors to expand the BMS. 

However, LoRaWAN sensors may have limitations regarding data transmission range, especially in buildings with thick walls that can obstruct signals. Battery life is also a consideration, as it determines the maintenance requirements for replacements. 

Cellular gateways

As LoRaWAN might not always be reliable inside buildings, cellular-based gateways offer a good alternative. These gateways can connect directly to power meters and building equipment that is not connected to the BMS. 

Cellular gateways offer broader coverage and higher bandwidth compared to LoRaWAN. They are also highly scalable, so it is easy to add new devices. However, its connectivity relies on existing cellular infrastructure which might not be available in remote locations, leading to connectivity issues. 

In summary, wired sensors, LoRaWAN sensors, and cellular gateways have their strengths and weaknesses. However, BMS systems can leverage a combination of these technologies to fit organizational needs.

Integrating existing systems with akenza

Integrating existing BMS with akenza presents an opportunity to enhance building automation capabilities. The versatility of the akenza IoT platform enables integration with both LoRaWAN/IP-based and wired sensor systems. This flexibility accommodates diverse infrastructure setups. 

One key advantage of the akenza platform is its compatibility with existing and new BMS controllers. This makes it interesting for retrofitting older buildings or upgrading current setups. 

With akenza’s data management capabilities, the platform serves as a central place for collecting, managing, and analyzing data from sensors. The controller can receive data from wireless sensors and use it for internal control, allowing the automation of building operations. An example of this is the control of HVAC systems based on the data received from occupancy sensors and temperature sensors. Or the adaptation of the lights in the building based on occupancy data.