Open Sytems are just that - a system that is open to allowing anyone to manufacture a competing product that will 'talk' on the same network as everyone else.

Simply put, open systems allow the end user to choose from a wider range of products and services than ever before, and it gives them the ability to mix and match from myriad product lines.

Benefits of Open Systems

Open systems are really about a platform choice. Dorb Controls offers both platforms, LonWorks and BACNet. These platforms are capable of supporting all the sub-systems in a facility including lighting, HVAC, access, security, elevator, blinds, emergency systems, environment monitoring, water supply, energy and others. Like any network, as an open system increases the number of devices, the power of the network, and therefore the benefits derived by the end-user, increase dramatically.

Typical Device Network Architectures

Overall, networks built with flat, open network traits deliver lower cost at integration and commissioning, have significantly lower life-cycle costs, allow for easier changes and enhancements, are more flexible, and are more adaptable to the end users.

An Open Control Protocol

An open, device networking communications protocol, such as EIA/ANSI 709.1 (the LonWorks Platform), or ANSI/ASHRAE 135-1995 (the BACnet Standard), assures manufacturers and end-users that they have made a technology decision that will be supported today and tomorrow. Thousands of companies today support the use of these protocols.

Flat Architectures

While there are many ways to design networks and control networks, for automated controls flat, peer-to-peer (P2P) architectures are best. P2P architectures lack single points of failures inherent in any hierarchical architecture. In such architectures, messages from one device must go first to a controlling master or gateway BEFORE the signal can get to the target device. Therefore, every communication between two non-master devices includes an extra step, or fault possibility. P2P designs, by contrast, allow direct communication between two devices eliminating the fault possibility of the master controller and removing a potential performance bottleneck. Further, device failures in a P2P design are much more likely to affect just the one device, not the potentially many as one finds in non-flat, not peer-to-peer architectures.

Device Level Interoperability

Any discussion of interoperability should begin with a definition of what it means. Simply, interoperability, in an automation network, is defined as the ability of devices from one manufacturer to understand and use data from another manufacturer’s device regardless of sub-system types or original purpose without the intervention of very costly gateways or protocol converters.

The benefits made possible by interoperability are many. Automation systems get simple (re: more reliable) since one sensor or device can be shared among many different sub-systems. They also get cheaper as fewer sensors/controllers are needed in the system and costs drop appreciably as parts are reduced and installation time and complexity decrease. Lastly, more can be done with an automation network when the devices are interoperable. For example, in response to access control reader data and daylight illumination sensors, the HVAC and lighting systems can automatically adjust the comfort and illumination levels in pertinent work areas based on individual preferences and energy costs. Lighting can be adjusted on a cubicle-by-cubicle basis for computer operators and occupants near windows- either automatically or through commands entered from a user’s PC via the corporate LAN. Heating and air conditioning can by similarly tailored.

Network Operating Systems

One way to look at a network operating system (NOS) is to look at the benefits derived from having one. In the case of automation systems for facilities, these can be many. At the installation stage, an NOS allows multiple sub-system installers to work simultaneously rather than sequentially. For instance, a lighting system could be commissioned at the same time as an HVAC system. An NOS also gives manufacturers a software architecture for creating simple plug-ins that allow integrators to easily see and configure various aspects of a device or system such as temperature set points or schedules.

After commissioning has been completed and the facility is operational, the NOS plays a vital role in providing network information including device health, operating characteristics, maintenance information and energy demand. The data is available for presentation through a variety of Human/Machine Interfaces (HMI) that can disseminate this information through client-server based architectures (e.g., Circon's Visual Integrator). The pervasiveness of the Internet now enables this information to be shared through any web aware client, driving down costs and greatly increasing value. Time critical actions can now be affected as the NOS allows remote access to the automation network to such an extent as to allow facility managers or integrators to perform the exact same tasks that they could if they were locally plugged into the network.

• The ability for owners and integrators to choose amongst best-of-breed, off-the-shelf components selected from among different manufacturers for both initial installations and enhancements down the road that are not tied to one manufacturer’s closed technology
• Lower system costs since the ability to choose fosters greater price competition
• Less complexity and fewer failure points through the elimination of gateways to bridge between sub-systems
• Lower cost deployments because it’s faster to deploy interoperable products than non-interoperable products
• The modularity of open systems enables changes and expansion to occur in a less-costly and less-complex manner
• Lower life-cycle costs, particularly from an operations and maintenance perspective
• Accurate, real-time information
• Enhanced end-user satisfaction
  
  

_____