How To Tell If Your Building Automation System (BAS) Is Really Open

BACnet binary code representing an open BAS configuration

A building’s automation system offers control of equipment such as HVAC, lighting, and security to create a safe and comfortable indoor environment for occupants.

Still, not every building automation system (BAS) is created equal. An ideal solution balances equipment performance, ease of use, and energy efficiency. The type of BAS—open or closed—makes a difference.

Most people prefer an open system as it gives you the freedom to customize building management at every level. Sometimes, however, it can be difficult to tell whether the BAS system you’re viewing is truly “open.”

“Open” vs. “Closed”

Years ago (when building automation was in its infancy), it was up to each equipment manufacturer to develop their own software. Naturally, they withheld the coding from competitors. These “proprietary” or “closed” control systems hinge on company-specific network protocols and programming tools—expansions or upgrades were only compatible with the same brand’s equipment.

The BAS manufacturer could effectively “lock-in” a building, which left owners without any competitive options for parts, maintenance, or servicing.

This situation led to buildings with multiple closed systems. It was unreasonable, with many different brands of equipment controlling different sections of a property. Building management became overly complicated, and maintenance budgets swelled due to the cost of maintaining multiple proprietary BAS systems.

An “open” system was the next reasonable step in BAS evolution, as it integrated equipment and devices from any manufacturer into a single system. These non-proprietary systems let a facility manager select building automation solutions based on functionality and price (regardless of brand or manufacturer).

Features of an Open System

An open BAS fully integrates a building’s equipment controls—it offers significant advantages over a closed, proprietary system.

An open system:

  • Allows you to manage equipment from multiple manufacturers
  • Can be used with both new and existing equipment
  • Uses a single software interface for all controls
  • Gives you the flexibility to source customized solutions
  • Lets you choose from a variety of service providers

How to Tell if Your System is Truly Open

Many vendors promote their BAS systems as “open,” but sometimes there are still proprietary features or functions.

For instance, a system may have open protocols to communicate over the same wiring. While at the same time, it may require proprietary programming software to integrate the controls for several buildings. This could be the case for campuses, such as universities and hospitals.

Several factors determine whether your system is really “open.” And you’ll have total flexibility, customization, and freedom of choice if it is.

Communications protocol

Most modern BAS systems utilize one or more open communication protocols such as BACnet, LonWorks, Modbus, or OPC. Legacy systems with vendor-specific language are closed.

Nowadays, forward-thinking manufacturers have replaced their proprietary language with an open protocol, so their devices can fit seamlessly into an open BAS.

Programming software

A vendor’s devices may use an open protocol for communication, but the knowledge to program the system could still be kept a secret. Even a minor task, such as swapping a bad output with a spare, requires a technician’s visit if this is the case.

To be considered open, the end-user should be able to program their system without having to turn to the manufacturer for support.

Product availability

Many vendors claim to have “widely available parts”; however, the only way to order them is through a specific, local branch distributor. This means a building owner looking for spare parts is, in reality, tied to a single source.

Only when parts are available from a selection of sources is a BAS genuinely free of vendor control.

Local service companies

A service provider supporting a particular manufacturer may only operate within a specific territory. And if you buy that manufacturer’s equipment AND happen to be outside of the service region, you may have trouble securing technical assistance.

With an open system, you can choose the BAS contractor whose services you like best, regardless of which brand of equipment you have.

User interface

In a closed system, it’s typical to access the BAS controls through a designated physical terminal or proprietary graphical user interface (GUI).   Almost all modern systems now offer remote access to the system over the internet.

An open BAS allows secure remote access to the system through any standard web browser. Off-site management enables quick response and makes it easy to find an expert for troubleshooting and support.

Read More: Understanding Proprietary and Non-Proprietary BAS

Conexus Supports Open Systems

At Conexus, we believe our customers should be able to manage their BAS system independent of any one service provider or vendor. We’re firm proponents of open systems and work to bring our clients the latest smart building technology.

Are you concerned about a lack of choices regarding your building automation system?

Partner with the experts at Conexus and discover how we’ll work together to find an open building automation solution that fits your needs.

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