1. BACnet Basics Ben H. Dorsey III VP, Marketing & Communications KMC Controls, Inc.

2. Preview BACnet—the standard (for the techie types) BACnet—the standard BACnet—the community (for everyone) BACnet—the community BACnet—and you (hey, for you) BACnet—and you 2

3. Caution BACnet is BIG 3

4. Part 1 BACnet—the standard

5. What is BACnet? An open standard A data communications protocol An acronym: Building Automation and Control Networks A means of automating buildings and integrating building systems A way of life! 5

6. So... BACnet is a data communications protocol and an agreed-upon set of rules for creating interoperable networks of building systems. 6

7. Encompassing... Mechanical systems HVAC Central Plant (Chillers, Boilers, Large Air Handlers) Lighting Perimeter and Object Security Fire and Life Safety Elevators The integration of all of the above. 7

8. Who did it? A working group (standard project committee) of the American Society of Heating, Refrigerating and Air- Conditioning Engineers (ASHRAE). Began work in 1987 under tremendous opposition (some said it would NEVER be done). Published as a standard in 1995. Supported and maintained by ASHRAE Standing Standard Project Committee 135. 8

9. It’s Alive!!! By design, the standard is under continual revision. First published in 1995. In recent times, most manufacturers’ products have been designed to the 2008 edition of standard. 9

10. Not a Reactive Process Addenda are issued as the committee works. Public review and comments are mandatory and common. So, for example, when 2008 was issued, it consisted of 2004 + previously issued addenda. (No surprises.) 10

11. What the Standard Defines In essence, the standard defines the messages that devices exchange and how they are delivered. 11 message transport

12. Further... The rules of the protocol apply to – Electrical signaling – Addressing – Network access (master/slave, peer-to-peer) – Error checking – Flow control – Message sequencing, segmentation, checkpointing – Presentation format (compression, encryption) – Message format 12 Source: Mike Newman, BACnet pioneer

13. Pyramid Scheme BIBBS Services Devices Objects Properties 13 The protocol can be viewed as a matrix of layers.

14. Properties BIBBS Services Devices Objects Properties 14 The nucleus to the BACnet atom—the smallest piece of BACnet information Properties can be read and written. Properties can provide command control. They consist of names and values.

15. Properties Example: high_limit = 78.0 The standard requires some properties; other properties are optional; still others can be proprietary. Required properties must be implemented for each object type. Optional properties do not have to be implemented, but if they are, they must conform to the specification. 15

16. Property Identifiers Property types 0 – 511 are reserved as standard. 166 of these are currently defined in the BACnet specification. Property types above 511 are proprietary and unique to the vendor. The Vendor ID property is used to identify the manufacturer. 16

17. Objects BIBBS Services Devices Objects Properties 17 Objects are the fundamental building blocks (atoms) of the standard. Objects represent data that originates in physical inputs, physical outputs, or software processes. Each BACnet Object possesses a number of properties.

18. Object Types Binary InputBinary OutputBinary ValueAnalog InputAnalog Output Analog ValueMulti-state Input Multi-state Output Multi-state Value Averaging PID LoopTrend LogCommandCalendarSchedule Life Safety Zone Life Safety Point Notification Class Event Enrollment Program FileGroupDevicePulse Converter Accumulator 18 The standard specifies many types of objects:

19. Objects Vendors can implement proprietary object types. When they do so, they use standard data types to promote interoperability. 19

20. Object IDs Numerical identifier that combines object type and instance number. Object types 0 – 127 are reserved to identify standard BACnet objects. Object types 128 – 1023 are used to identify proprietary objects. 20

21. Object IDs BACnet devices will support any mixture of object types up to a limit of 4,194,303 instances. Object IDs are typically referred to in this manner: Analog Input, 5 21

22. Objects—Summary Objects standardize the organization of data to facilitate the exchange of data between different vendors’ products. 22

23. Devices BIBBS Services Devices Objects Properties 23 There are several device types or profiles specified by the standard: – Advanced Operator Workstation (B-AWS) – Operator Workstation (B-OWS) – Operator Displays (B-OD) – Building Controller (B-BC) – Advanced Application Controller (B-AAC) – Application Specific Controller (B-ASC) – Smart Actuator (B-SA) – Smart Sensor (B-SS) – Other BACnet devices (B-Oth)

24. Services BIBBS Services Devices Objects Properties 24 Think of BACnet services as the messages that BACnet devices send to each other. Some services read and write properties of one or more objects. Other services send notification of alarms or special events. Still other services read and write files.

25. Services BACnet services follow a Client-Server model. – A BACnet client is a device that requests a service – A BACnet server is a device that performs a service 25

26. Categories of Services Alarm and Event – Routing & event notification File Access – Accessing & manipulating files contained in devices Object Access – Read and write properties – Create and delete objects – Manipulate lists of data Remote Device Management – Remote monitoring and control of devices Virtual Terminal – Used by a client user to establish a connection to an application program server in another BACnet device. 26

27. Services—ReadProperty 27 We wish to read the present value for an analog input called “SPACE_TEMP” Service= ReadProperty ‘ObjectIdentifier’ = (Analog Input, Instance 5) ‘PropertyIdentifier’ = Present_Value Operator Workstation (client) MS/TP AAC (server) Service= ReadProperty ‘ObjectIdentifier’ = (Analog Input, Instance 5) ‘PropertyIdentifier’ = Present_Value ‘Value’ = 72.3 Assuming the target machine can locate the object with this ID and the requested properties, the result would be: The result indicates that the present value of “SPACE_TEMP” is 72.3 Source: ANSI/ASHRAE Standard 135-2004, page 494

28. BIBBS Services Devices Objects Properties 28 BACnet Interoperability Building Blocks BIBBS are collections of services BIBBS define 5 areas of interoperability: – Data Sharing – Alarm and Event Management – Scheduling – Trending – Device and Network Management BIBBS

29. BIBBs Summary Example: B-BC Data Sharing – Ability to provide the values of any of its BACnet objects – Ability to retrieve the values of BACnet objects from other devices – Ability to allow modification of some or all of its BACnet objects by another device – Ability to modify some BACnet objects in other devices Alarm & Event Management – Generation of alarm/event notifications and the ability to direct them to recipients – Maintain a list of unacknowledged alarms/events – Notifying other recipients that the acknowledgement has been received – Adjustment of alarm/event parameters Scheduling – Ability to schedule output actions, both in the local device and in other devices, both binary and analog, based on date and time Trending – Collection and delivery of (time, value) pairs Device & Network Management – Ability to respond to queries about its status – Ability to respond to requests for information about any of its objects – Ability to respond to communication control messages – Ability to synchronize its internal clock upon request – Ability to perform re-initialization upon request – Ability to upload its configuration and allow it to be subsequently restored – Ability to command half-routers to establish and terminate connections 29

30. Transport Options BACnet IP BACnet Ethernet (8802-3) Master Slave/Token Passing (MSTP) ARCnet LonTalk Point-To-Point (PTP) 30

31. Transport Comparison BACnet IP Popular, fast. No real performance difference between this and 8802-3. Use BBMD or PAD router to get across an IP router. Broadcast issues. BACnet 8802-3 Popular, fast. No real performance difference between this and IP. Cannot get across IP routers. MSTP Very popular, especially as a low-level bus technology for AACs and ASCs. Uses EIA- 485 signaling over twisted pair wiring. Lower performance. 31

32. BACnet Layers vs OSI Layers 32 Standard OSI Reference Model Application Presentation Session Transport Network Data Link Physical Equivalent OSI Layer Application Network Data Link Physical BACnet Layers BACnet Application Layer BACnet Network Layer ISO8802-2 (IEE 8802.3) Type 1 Source: ANSI/ASHRAE Standard 135-2004, page 9 ISO8802-3 (IEE 802.3) ARCNET LonTalk MS/TP EIA-485EIA-232 PTP

33. Auxiliary Devices Routers – Useful when networks using different BACnet transport options need to exchange data.* 33 Operator Workstation on BACnet IP network Router BACnet MSTP Controller Network *This concept is referred to as “Internetworking.”

34. Auxiliary Devices Gateways – Useful when devices on a BACnet network must exchange data with devices on a non- BACnet network.* 34 BACnet network Gateway Proprietary Network *This is also Internetworking.

35. So, what’s the difference? A router is really a pass-through device. It doesn’t change the form or content of the message but just the packaging—much like repackaging a standard USPS letter for sending via Fedex. A gateway has to translate and is inherently more complex. It opens the letter, translates it into a second language, and puts it back into some sort of envelope and sends it on. 35 Source: Mike Newman, BACnet pioneer

36. How Does BACnet Work? 36 Transport System LANs Internetworking Representing Information Objects Making Requests and Interoperating Services Application Language Source: David Fisher, PolarSoft

37. Typical System View 37 Management Level Integration Level Field Controller Level Operator Workstation Ethernet or IP LAN RouterGateway MSTP LAN Proprietary LAN ASCs & AACs Application Level Proprietary Controllers BACnet-enabled Applications & other apps

38. Part 2 BACnet—the community

39. Engineers & Educators Members of ASHRAE – 12 standard regions with 7-16 chapters in each – Beyond America, ASHRAE reaches into Canada and South America. – Beyond the Americas, ASHRAE reaches into Hong KongMiddle EastScotland Malaysia IndiaWales Philippines AfricaIreland Singapore Europe Taiwan Scandinavia Thailand England 39

40. SSPC 135 Consists of working groups: – Applications – Lighting Applications – Life Safety & Security – Network Security – Objects & Services – Utility Integration – XML & Web Services 40

41. Manufacturers, Integrators, Owners BACnet International – Formed in January 2000 to "encourage the successful use of the data communication protocol, "BACnet", in building automation and control systems, through interoperability and compliance testing, educational programs, and promotional activities." 41

42. Corporate BI Members (partial) 42

43. Plugfests Among the many initiatives undertaken by BACnet International are interoperability workshops or “plugfests.” Dozens of member companies routinely take part in these 3-day events for validating product interoperability. 43

44. Interests Groups BIGs consist of users, integrators, manufacturers, contractors, and other interested parties. 44 BIG-SUBIG-FI

45. BTL BACnet Testing Laboratories – Established under direction and continued supervision of BACnet International in Feb 2000 – “Our goal is to improve interoperability between BACnet products through a combination of BTL lab testing, multi-vendor interoperability testing, and adherence to the BTL's device implementation guidelines.” (former BTL Manager) – Lists products by issuing mark 45

46. BTL Has freedom to make requirements above and beyond the minimum requirements specified in the standard. Manufacturers are given pretest guidelines. Requires an extended engineering commitment of manufacturers. 46

47. Part 3 BACnet—and you

48. BACnet & You Why go BACnet? Engineer & owner considerations Is it really interoperable? What’s next? 48

49. BACnet Benefits It is an accepted standard domestically (ASHRAE/ANSI 135-2008), in Europe (CEN TC 247), and worldwide (ISO 16484-5). It was developed specifically for building systems. While HVAC is at its roots, the standard nicely incorporates other integrated functions. 49

50. BACnet Benefits It can be implemented on low-cost networks (dedicated or shared) and is extremely flexible in LAN types. BACnet devices are cost-competitive with long-standing proprietary devices. The standard specifically provides for scheduling, trending, and alarming. 50

51. BACnet Benefits It is easily scalable at all levels for any size job. It is completely open and not dependent on specific hardware. It provides for automatic device discovery (saving installation costs). 51

52. BACnet Challenges It does not specify hardware configuration. Therefore, configuration tools (required for initial device setup) vary by manufacturer. No standard application types are defined; therefore, it’s not yet plug-n-play. 52

53. Considerations Become familiar with PICS – Protocol Implementation Conformance Statements – Defined format – Specify device type, BIBBS supported, Object Types supported, and Data Link layer transport options. – Required for each BACnet device – Available to you 53

54. Considerations Become familiar with PICS. Look for “native” BACnet. – Native BACnet refers to a device that inherently represents data in BACnet format and communicates utilizing BACnet messaging. Native BACnet devices were designed from the ground up as BACnet (as opposed to adding BACnet functionality to a previously designed product). 54 BACnet “Native” BACnet

55. Considerations Become familiar with PICS. Look for “native” BACnet. Specify BTL listed products. – This is the BACnet community’s seal of approval. 55

56. Considerations Become familiar with PICS. Look for “native” BACnet. Specify BTL listed products. Demand training. 56

57. Is it really Interoperable? 57

58. Interoperability Case Studies We’re populating our web site and the web site of BACnet International with numerous case studies that illustrate multi-vendor interoperability and systems integration: – http://www.kmccontrols.com/products/projectshome.aspx http://www.kmccontrols.com/products/projectshome.aspx – http://www.bacnetinternational.net/success/stories.php http://www.bacnetinternational.net/success/stories.php One such KMC project was awarded “Best in Show” by BACnet International as the top interoperable project published on the BI web site in 2010: – Kuwait Oil Company Project Kuwait Oil Company Project 58

59. Where is BACnet Going? BACnet support of IP communications lays the necessary groundwork for enterprise- wide challenges. To meet these challenges, however, will require greater utilization of Internet protocols developed in the IT realm. 59

60. XML & Web Services Not really applicable to field-level controllers but high- level communications. XML provides for examining high-level data while not being dependent on the communication protocol of the BAS, such as BACnet. So, BACnet manufacturers need to support XML in the operator workstation, for example. Further, web services, such as.NET, provide for greater possibilities in information exchange. The SSPC 135 XML Working Group is defining how data can be exchanged consistently between building automation systems and other enterprise management systems. 60

61. Further Resources www.bacnet.org www.bacnetinternational.org 61

62. So, what are you waiting for? 62