|Interoperable Building Automation Networks|
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3. Business Case
6. Next Steps
- In the early 90’s an effort to “standardize or open up” building automation systems was started. Two efforts gained the most traction and momentum.
- BACnet- Started as a committee within ASHRAE to create standards for system to system communication. en.wikipedia.org/wiki/BACnet.
- LonWorks- Started as a technology created by Echelon to provide an open standard for device to device communication. en.wikipedia.org/wiki/LonWorks
- BACNet - a Data Communications Protocol for Building Automation and Control Networks. It is an ASHRAE, ANSI, and ISO standard protocol. BACNet was developed within ASHRAE and therefore started as an HVAC standard though it now also covers lighting control, access control, and fire detection systems and their associated equipment.
- C-Bus - A proprietary communications protocol for home and building automation that can handle cable lengths up to 1000 meter using Cat.5 cable. C-Bus was created by Clipsal for use with its brand of home automation and building lighting control system. C-Bus is used in the control of home automation systems, as well as commercial building lighting control systems. Unlike the more common X10 protocol which uses a signal imposed upon the AC power line, C-Bus uses a dedicated low-voltage cable or two-way wireless network to carry command and control signals. This improves the reliability of command transmission and makes C-Bus far more suitable for large, commercial applications than X10.
- DALI – Digital Addressable Lighting Interface – An open standard protocol for the controlling of lighting in buildings, such as electrical ballasts and dimmers. DALI was established as a successor for the still market dominating 1-10v and an open standard rival to Digital Signal Interface (DSI), on which it is based. DALI is standardized in accordance with IEC 60929, standard for fluorescent lamp ballasts. Each piece of operating equipment with a DALI interface can be communicated with over DALI individually. Using a bi-directional data exchange, a DALI controller can query and set the status of each light. The maximum number of devices on a DALI loop is 64.
- DeviceNet - A communication protocol used in the automation industry to interconnect control devices for data exchange. It uses Controller Area Network as the backbone technology and defines an application layer to cover a range of device profiles. Typical applications include information exchange, safety devices, and large I/O control networks.
- EnOcean - a German wireless, energy harvesting technology used primarily in building automation systems. It is not set out for international, European or national standardization; however, EnOcean GmbH is offering its technology and licenses for the patented features under license within the EnOcean Alliance framework.
The concept was developed to enable batteryless sensors and switches for building automation. A spin-off company of Siemens AG founded in 2001, that is venture funded. It is a technology supplier of self-powered modules (transmitters, receivers, transceivers, and energy converters. The company has developed a technology that is based on the efficient exploitation of slight changes in the environmental energy using the principles of energy harvesting. The company’s products (such as sensors and radio switches) have no battery and are engineered to operate maintenance-free. The signals of these sensors and switches can be transmitted over a distance of up to 300 meters. The most pervasive example of a product stemming from the proprietary RF protocol is the battery-free wireless light switch. EnOcean is a wireless partner of Lonmark. 80% of the Wireless Lighting Solutions at Lightfair 2009 were EnOcean-based.
- Fieldbus (Wikipedia)- A family of industrial computer network protocols used for real-time distributed control, now standardized as IEC 61158. A complex automated industrial system usually needs an organized hierarchy of controller systems to function. In this hierarchy there is usually a Human Machine Interface (HMI) at the top, where an operator can monitor or operate the system. This is typically linked to a middle layer of programmable logic controllers (PLC) via a non time critical communications system (e.g. Ethernet). At the bottom of the control chain is the fieldbus which links the PLCs to the components which actually do the work such as sensors, actuators, electric motors, console lights, switches, valves and contactors. Fieldbus works on a network structure which typically allows daisy-chain, star, ring, branch, and tree network topologies. Previously computers were connected using RS-232 (serial connections) by which only two devices could communicate.
- Gateways – A network node equipped for interfacing with another network that uses different protocols with translation tables. The job of a gateway is much more complex than that of a router or switch. Typically, a gateway must convert one protocol stack into another. A gateway may contain devices such as protocol translators, impedance matching devices, rate converters, fault isolators, or signal translators as necessary to provide system interoperability. It also requires the establishment of mutually acceptable administrative procedures between both networks. Gateways may take several forms: embedded in routers, software solutions or other control devices. A gateway gives you a limited view into a system. A very common transition point between the different protocols is between the building controls level and the IP level.
- KNX (Wikipedia)– Pronounced Konnex , European Installation Bus (EIB) – now the mainstay of KNX– originally developed by Siemens. The bulk of the products originate from German manufacturers and are used within Germany and its close geographical neighbors. However, within that area, there is a high degree of penetration within the commercial building sector, less so in the residential sector, and this is due, in large part, to the successful inclusion of EIB technology in the education and training programs for professional electrical installers.
- LonWorks (Wikipedia) – A networking platform specifically created to address the unique performance, reliability, installation, and maintenance needs of control applications. The platform is built on a protocol created by Echelon Corporation for networking devices over media such as twisted pair, power lines, fiber optics, and RF. It is popular for the automation of various functions within buildings such as lighting and HVAC; LonWorks refers to the entire technology
- Has database standard (LNS) while BACNet does not
- Started as an HVAC standard
- LonTalk – LonWorks Protocol
- LonMark – LonWorks Standards Group
- Modbus – Modbus Standard in the electrical world. A serial communications protocol published by Modicon in 1979 for use with its programmable logic controllers (PLCs). It has become a de facto standard communications protocol in industry, and is now the most commonly available means of connecting industrial electronic devices. Modbus filled some of the needs of the building-automation community prior to BACnet but, coming from the industrial world, it was not originally designed for the needs of buildings data. Modbus may be used to integrate with switch gear in a building. The main reasons for the extensive use of Modbus over other communications protocols are:
- It is openly published and royalty-free
- Relatively easy industrial network to deploy
- It moves raw bits or words without placing many restrictions on vendors
- NIST has recognized BACnet ANSI ASHRAE 135-2008/ISO 16484-5 in initial list of 16 Smart Grid standards.
- True building integration means finding commonalities between building systems and using the appropriate communication protocols to program them. This provides cooperative sequences of operations that offer increased value to the building owner. Before open architecture communications protocols, building automation was controlled by proprietary control solutions. Solution providers manufactured the building control systems, developed the application software, and charted product development, deployment and product line diversity
- BACNet, LONWorks and Modbus are similar in that their primary purpose is to facilitate communication between devices in a building. Another common thread is that they all conform to European Open System Interconnection standards and provide a migration path for data to be communicated to higher level devices.
- The fundamental difference between the protocols is that BACnet was developed as a system-to-system interoperable protocol originally designed for HVAC systems to communicate with each other, while LonWorks was developed as an interoperable protocol at the product and device level.
- Another primary difference between BACnet and LonWorks is that the BACnet standard does not include hardware, while the LonWorks protocol is embedded in its neuron chip.
- BACnet, LonWorks and Modbus all differ in their approach to how their target customer base might choose to implement integrated systems and devices.
- Modbus supports a more industrial methodology. One of Modbus’ primary strengths is that it is a master/slave protocol which means one device is set up to gather data, and the other devices provide the data. While Modbus is simpler to implement, it is not as sophisticated a protocol and does not address scheduling, alarming and trending issues as BACnet and LonWorks do.
- BACnet focuses on the integration of multiple buildings that are, for the most part, stand-alone
- LonWorks is used to integrate many small, intelligent devices arranged into groups that represent functions, buildings or even geographic areas.
- Unfamiliarity - Enterprise IT staff are seldom familiar enough with building controls to know how to integrate them and whether those systems could compromise the network. Only through training and experience will they have the skills to securely bring together such dissimilar systems as Internet protocol and LonTalk, for example.
- Incompatibility - Even for skilled IT professionals, some systems simply are challenging to integrate. Many protocols are not up to enterprise IT security standards, or force integration at a level too high (excessively abstract) or too low (causing data overload) to capture the benefits of the synergy.
- Energy Requirements - LonWorks designed around neuron, too energy intensive for wireless
- Interoperability - Common Standards continue to evolve (BACnet, LonWorks, Modbus) Many technology subsets may exist beneath one “head end”, making interoperability difficult
- Sole-Source Lock - Prevents competitive bidding and best-in-breed product selection
- Merging Power and Industry. As more customer-centric applications like real-time pricing, distributed generation and micro-grids are deployed; utilities must take more of an interest in the industrial automation world. What was previously a one-way relationship must become a partnership as customers become active contributors to the operation of the power system.
- Encapsulate LonWorks over IP
- ASHRAE is also working to extend BACnet to support wireless Zigbee networks
- Another future area to explore is cost-effective, small device networking. The market is moving toward lower cost, smaller device communication. The area that offers the best opportunity is deploying low-cost wireless and powerline communications for cost-effectively integrating simpler devices.
- Cimetrics, Boston, MA, A pioneer in open system communication for building automation for more than 10 years. By developing and promoting BACnet, the world’s standard building automation protocol, Cimetrics established itself as the premier supplier of communication technology to the building automation industry.
- Echelon (NASDAQ: ELON), San Jose, CA - Designs control networks to connect machines and other electronic devices, for the purposes of sensing, monitoring and control.
Echelon's LonWorks platform for control networking was released in 1990 for use in the building, industrial, transportation, and home automation markets. Launched in 2003, Echelon's Networked Energy Services system is an open metering infrastructure.
Echelon provides the underlying network technology for the world's largest Advanced Metering Infrastructure (AMI) in Italy (See my case study xxx) with over 27 million connected electricity meters and more recently it won tenders to provide the NES System to several hundred thousand customers of utilities in Sweden and The Netherlands.
On May 8, 2012, Echelon introduced a new Control Operating System (COS)-enabled control module that, when coupled with Echelon's data concentrator and system software, enables electricity meter manufacturers to quickly and cost-effectively offer a comprehensive solution for automated metering and low voltage grid optimization. The new CPM 0600 control point module implements the Open Smart Grid Protocol (OSGP) and transforms the manufacturer's electronic meter into a smart meter plus grid sensor that leverages Echelon's proven, open standard, and multi-application energy control networking platform. The company also announced that leading meter makers in Asia, including Mitsubishi Electric Automation (Thailand) Co., Ltd., Korea's VIDCOM, Malaysia's Comintel, and China's Holley Metering, will offer solutions based on Echelon's platform.
Source: PR Newswire (http://s.tt/1bboD)
In the U.S., Echelon's powerline technology has been a liability. (It now has an RF option as well.) In some other parts of the world, powerline has cost, reliability and simplicity advantages.
Echelon makes an Edge Control Node that attaches to transformers. It acts as a communications hub (supporting multiple connectivity options) and as a concentrator. It collects data from the meters that are attached to that transformer. But it does two other important things. First, it can also collect data from other sensors. Second, it has enough intelligence to aggregate and preprocess the data. The node then sends along only what's needed – aggregated totals, exceptions, alerts, etc. This approach minimizes communications congestion.
- Echoflex Solutions - Squamish, British Columbia, Canada- Incorporated in 2005, Echoflex became one of the first companies in North America to begin developing products based on a new wireless technology from Europe called EnOcean. EnOcean is a unique technology; integrating innovations in harvesting and storing energy with low-power radio technologies
Echoflex develops automation solutions with energy conservation as a primary focus. To save energy, power that is being consumed today must be turned off when it is not needed. To achieve this goal efficiently and eliminate human intervention, automation must take a role in the process. The automation solutions that Echoflex develops are based on a distributed control model. Through distributing the control elements room by room or circuit by circuit, the density of the control mesh created increases making it more efficient in its goal and improving energy savings.
- LonMark – LonWorks Standards Group
- BACNet.org - Myths of LonWorks and BACnet Building owners and facility managers have long awaited the means to break the proprietary lock of the building control manufacturers. BACnet and. LonWorks are two protocols that arecompeting to be the key that unlocks the lock.
- Echelon - LonWorks Technology Overview
- Echelon's LonWorks Technology Internet Demo The purpose of this demo is to provide an interactive vehicle for you to experience the power of LonWorks control technology
- DALI Action Group -A working group set up by leading manufacturers and institutions in the field of digital lamp/luminaire control to promote DALI technology and applications
- David Fisher, Member ASHRAE - SeeingThe LightWith BACnet - Describes some features of BACnet for lighting applications that, as of November 2008, were not yet part of the standard, but are expected to be published soon. - BACnet Today