1. BACnet: An Overview
BACnet Overview. The “Buzz Words” include BACnet, LAN, LonTalk, etc. It seems that a great deal of people are talking about the open network technology of BACnet.
The intention of this presentation is to provide you with an overview of the different LAN technologies available for use with BACnet. It will also give you the familiarity with the terminology enough to make you “Dangerous” in the field.
This presentation provides some background as to why people are specifying BACnet systems, some history on the formation of BACnet, and the pros and cons of the transport protocols available for BACnet Objects. The discussion will end with a preview of the Simplex BACpac Portal.

2. Why BACnet?
This is a cartoon depiction of why the industry is so interested in BACnet. For one moment imagine that you are this on-duty Security Guard, required to keep track of the status of all the systems within a building, e.g., the fire alarm system, security system, HVAC system, etc. Today, utilizing different vendor’s proprietary systems forces building owners to install multiple head-end workstations. Imagine the potential for confusion that exists if multiple problems begin to occur within the building.

3. Integrated Network Systems
General Overview
Campus Network Today
Campus LAN
Campus
Police AC
Shop
Engineering
Physical
Plant
Building Management Supplier
Software
Bldg. 1
Access
Control
Gateways
Fire
Alarm
Security
Building
Management Supplier
This is a typical diagram of a campus Local Area Network (LAN), shown with interfaces to multiple systems. One key point to draw from this diagram, the Building Management Suppliers are controlling what manufacturers are brought in to supply other systems. As shown here, if the Building Management Supplier markets a Fire Alarm System or is affiliated with a particular manufacturer, the end user will be forced to use the provided system due to development costs and/or availability to create a third party interface connecting such systems.

4. Open Network Topology General Overview HVAC Lighting Security Access
Future Campus Network
Physical
Plant
Campus LAN
Bldg. 1
Campus
Police AC
Shop
Engineering
HVAC
Ideally, an open network system would lead to a solution not allowing Building Management Suppliers to drive and dictate which systems and manufacturers will be selected.
One important note of concern: Because Fire Alarm Systems are driven by local and state adopted building and fire code, true open networks require much care and concern when interfacing Fire Alarm Systems to Building Management workstations. This may lead to restrictions and strict requirements imposed on other interfaced systems.
For now, Fire Alarm Systems may have to rely on only sending annunciated information to workstations rather than allowing them to receive commands.
Lighting
Security
Access
Fire Alarm

5. Economical Reasons Different manufacturers;
Single system head-end, multi-access;
Well defined system responsibilities;
Reduced manpower;
Training;
Use of existing network infrastructure.
There is a monetary impact of training people to monitor systems within a building.

6. Technical Reasons Sensor reuse
Heat;
Lighting.
Smoke Control System Equipment (UUKL) data passing.
Coordination of all control systems
Alarm resolution;
Report generation;
Multi-sensor correlation.
Flexible system design.
UUKL is another interesting area that may drive this move to open network systems. UUKL is the section of the UL Directory on Fire Protection Equipment that deals with listing of Smoke Control System Equipment.
As defined on page 271 of the 1998 Edition, “The products covered by this category are intended to be installed in conjunction with heating-ventilating-air conditioning (HVAC) equipment to form a system for controlling the flow of smoke in a building during a fire condition in accordance with Smoke Control Systems, NFPA 92A or NFPA 92B. They are intended to perform specific functions related to a smoke control system. This function and the interconnection to other smoke control equipment, as well as HVAC equipment, are described in an installation document attached to the product or referenced in the marking on the product.
We are finding more and more that AHJ’s are requiring UUKL listed Smoke Control Systems. With a BACnet interface, this will allow Simplex to provide a direct interface as the Fire Alarm Panel to a listed Smoke Control System.
On a side note, we have a UUKL listing for the 4020, 4100, 4100U and 4120 panels.

7. Integrated Network Systems
HVAC
Panel
UUKL
Panel
HVAC
Panel
Lighting
Panel
Control Panel
Control Panel
Control Panel
UUKL Panel
LAN
FIRE Panel
FIRE Panel
Control Panel
On the Local level, ideally all systems would “live” and communicate on the same LAN. The systems would cooperate and be capable of interfacing to a single head-end workstation.
Control Panel
Vertical Lift
Panel
Security
Panel
FIRE
Panel
FIRE
Panel

8. Desired View - Global Access
Single Building Level
Campus Level
World Level
Campus
Network
Expansion to global systems is a definite possibility. This would prove advantageous for a corporation with multi-city offices to keep in contact.
World
Net

9. Fire Control Stays Local
4120 Network
4020
4020
Control
4020
4020
4020
Campus
WAN
Control
4100
4002
4100
FCP
But what about Fire? There are code issues and legitimate concerns when systems are allowed to completely interact and control other systems. In the case of Fire Alarm Systems, there are severe ramifications of allowing one system to dominate another; or allowing the workstation at one location to control the FA system in another.
With the use of the Simplex BACpac Portal the control of the FACP stays local within the associated network. It provides a read only interface to the BACnet Workstation. This will allow annunciation of selected points.
4100
4020
Control
4020
4020
Control
4020
MAPNET

10. Background Typical applications: Future is virtually limitless.
HVAC controls;
Lighting controls;
Security (access control);
Fire detection systems;
Fire suppression systems;
Elevators;
Other control equipment and systems.
Future is virtually limitless.
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11. Bacnet Application Concepts
Facilitate the use of digital control technology.
Defined data protocols;
Application services.
Abstract object oriented information:
Input & output values (Binary, Analog, Multi-stage);
Text string values;
Schedule information;
Alarm & event information;
Files;
Control logic.
Object -- access to information without knowing details.
Tyco Safety Products is a member of the BACnet committee
BACnet has 18 defined objects and 5 Defined Services (#’s refer to ANSI/ASHRAE chapter)
Analog Input 12.1
Analog Output 12.2
Analog Value 12.3
Binary Input 12.4
Binary Output 12.5
Binary Value 12.6
Calendar
Command
Device
Event
File Object
Group Object
Loop Object
Multi-State Input Obj 12.14
Multi-State Output Obj 12.15
Notification Obj
Program Obj
Schedule Obj
Alarm & Event 13
File Access 14
Object Access 15
Remote Device GMT 16
Virtual Terminal 17

12. Building Automation Control BACnet
OSI Basic Reference Model
BACnet Layers 7
Applications Layer 6
Presentation Layer
BACnet Application Layer 5
Session Layer
BACnet Network Layer 4
Transport layer
ISO (IEEE 802.2)
Type 1
MS/TP
PTP 3
Network Layer
ISO
(IEEE 802.3)
ARCNET 2
data link layer
EIA-485
EIA-232 1
The International Organization for Standardization (ISO) has been tasked to develop an assortment of computer communications standards. This development is known as Open Systems Interconnection (OSI). Its purpose is to design and implement the interconnection of open computer systems. The first open system standard approved was the Basic Reference Model (ISO 7498).
The OSI model divides a very complex problem of communication between computers into smaller easier defined pieces. Each of these pieces (defined here as layers) has a specific function providing services to the layers above and relying on the layers below to carry out these services.
Application Layer - handles the interface with the user’s application program.
Presentation Layer - converts codes, encrypts/decrypts, or reorganizes data.
Session layer - manages dialog, synchronizes data transfers with checkpoints.
Transport Layer - provides end-to-end error checking and data segmentation.
Network Layer - Establishes logical circuits and routing between machines.
Data Link Layer - controls orderly access to the physical medium.
Physical Layer - Transmits and receives individual bits on the physical medium.
Physical Layer
BACnet is a loosely coupled protocol allowing for greater
flexibility in the data link layer -- though well defined in the
network and application layer for information interoperability

13. BACnet Application Protocol
Data Representation
Objects.
Application Services
Ways to access the data.
Network Services
Methods to have access to devices on the network.
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14. Binary Input Object PROPERTY BACnet EXAMPLE
Object_Identifier Required (Binary Input, Instance 1)
Object_Name Required "MAPNET point M1-35"
Object_Type Required BINARY_INPUT
Present_Value Required ACTIVE
Description Optional “First Floor ZAM"
Device_Type Optional “ABC Pressure Switch"
Status_Flags Required {TRUE,FALSE,FALSE,FALSE}
Event_State Required OFFNORMAL
Reliability Optional NO_FAULT_DETECTED
Out_Of_Service Required FALSE
Polarity Required NORMAL
Inactive_Text Optional “Static Pressure OK”
Active_Text Optional “High Pressure Alarm”
Change_Of_State_Time Optional (23-MAR-1995, 19:01:34.0)
Change_Of_State_Count Optional 134
Time_Of_State_Count_Reset Optional (1-JAN-1995, 00:00:00.0)
Elapsed_Active_Time Optional 401
Time_Of_Active_Time_Reset Optional (1-JAN-1995, 00:00:00.0)
Time_Delay Optional 10
Notification_Class Optional 3
Alarm_Value Optional ACTIVE
Event_Enable Optional {TRUE,FALSE,TRUE}
Acked_Transitions Optional {FALSE,TRUE,TRUE}
Notify_Type Optional ALARM
This is a modified example from page 420 of ANSI/ASHRAE It is a representation of a possible Binary Input Object that might be sent from the FACP to the BACpac Portal.

15. BACnet Services Alarm & Event 13 File Access 14 Remote Device MGT 16
Ack Alarm C
Conf COV Notification C
Conf Event Notification C
Get Alarm Summary C
Gen Enrollment Sum C
Subscribe COV C
Unconfirm COV Not U
Object Access 15
Add List Elem C
Remove List Element C
Create Obj C
Delete Obj C
Read Prop C
Read Prop Cond C
read Prop Multiple C
Write Prop C
Write Prop Multiple C
File Access 14
Atomic Read File C
Atomic Write File C
Remote Device MGT 16
Device Comm Control C
Confirm Private Transfer C
unconfirmed Private Transfer U
Conf Text Msg C
UnConf Text Msg U
Time Synch U
Who-Has U
I-Have U
Who-IS U
I-am U
Virtual Terminal 17
VT Open C
VT Close C
VT Data C
Alarm & Event Services: The conceptual approach and application of services used in BACnet to manage communications related to events. Events are changes of value of certain properties or certain objects, or internal status changes, that meet predetermined criteria. The tree mechanisms for managing events are: change of value reporting, intrinsic reporting, and algorithmic change reporting.
File Access Services: The set of services used to access and manipulate files contained in BACnet devices. The concept of files is used here as a network-visible representation for a collection of octets of arbitrary length and meaning; it is abstract and does not imply the use of disk, tape or other storage devices.
Object Services: Divided into nine application services that collectively provide the means to access and manipulate the properties of BACnet objects. A BACnet object is any object whose properties are accessible through this protocol regardless of its particular function within the device it resides.
Remote Device Management Services: Used by a client BACnet-user to instruct a remote device to stop initiating and responding to application layer protocol data units on the communication network or inter-network for a specified duration of time.
Virtual Terminal Services: Used by a client BACnet-user to establish a connection to an application program server in another BACnet device. The purpose of this connection is to facilitate the bi-directional exchange of character-oriented data.

16. BACnet Functional Groups
FUNCTION GROUP DESCRIPTION
Clock Capabilities generally associated with having a clock.
Hand-held Workstation Hand-held or portable workstation capabilities.
Personal Computer Workstation Main operator workstation capabilities.
Event Initiation Detect and generate alarms and events.
Event Response Ability to respond to alarms and events.
COV Event Initiation Ability to initiate change-of-value notifications.
COV Event Response Subscribe to and receive change-of-value notifications.
Files Capability to read, write, upload and download files.
Reinitialize Ability to be reinitialized from remote device.
Virtual Operator Capable of providing operator side of virtual terminal session.
Virtual Terminal Capable of providing server side of virtual terminal session.
Device Communications Device Communication Control Service request execution supported.
Time Master Able to initiate Time Synchronization Service request.
Some BACnet object types and application services are classified in functional groups. Each functional group defines a combination of application services and standard object types that are required for BACnet to support the communication requirements of that particular building automation function. BACnet functional groups represent capabilities that may be added to devices of any conformance class. Functional groups are intended to provide guidance to people designing and specifying multi-vendor building automation systems.
For the application services included in each functional group, a distinction is made between a requirement for the capability to initiate a service request and a requirement for the capability to execute a service request.

17. BACnet Protocol Control Status BACnet UDP port - X’BAC0’ BACnet Net
Set host
4120
BACnet
CPP
EQB, RQB
UDP
port - X’BAC0’
BACnet Net
Virtual layer IP
4120 NM
A visual representation of the transport media for the BACnet protocol as compared to the transport media of Simplex FACPs.
SLIP, PPP
4120 DL
Ethernet
LonTalk
Arcnet
Master
Slave
Token
Passing
HDLC, etc.
Phone
Network
RS485
232
RS485
RS485
232

18. Data Link Transport Formats
ISO (IEEE 802.3) or Ethernet.
ANSI/ATA or ARCNET.
Master Slave/Token Passing or MS/TP.
Point-to-Point or PTP.
LonTalk - proprietary technology developed by the Echelon Corporation.
There are 5 transport formats that BACnet protocol can travel on, listed above by their technical names, as well as, other more common abbreviations.

19. Ethernet Pros Cons Internat’l standard. Exists in most bldgs.
Ease of interface to PC’s.
No develop. tools.
Very fast comm. (10 to 100Mbps).
Transport media (unshielded twisted pair (UTP), coax, fiberoptic).
Cons
High cost.
Distance limitations.
Non-Deterministic (contention based).
Ethernet is the most widely used transport protocol. It provides very high performance for modest cost. The Ethernet chip cost has dropped considerably in recent years, but the technical limitations including physical signaling and high speed, require the need for hubs and repeaters. These add to the cost of the system, driving it up significantly.

20. ARCNET Pros Cons ANSI standard. Deterministic. Scaleable speed.
No develop. tools.
High performance; medium cost.
Very fast comm. (150K to 7.5Mbps).
Transport media (UTP, coax, fiberoptic).
Cons
Single source chip.
Too costly for low-end unitary controllers.
Distance limitations.
ARCNET is a LAN that implements a token-passing scheme, which implements chips that control the network management. The speed is scaleable implementing media from EIA-485 at 150Kbps to coax or fiber at 7.5Mbps.

21. MS/TP Pros Cons ANSI standard. Deterministic. Low cost.
Implementation in single chip microprocessors.
Cons
Transport media (EIA-485).
Limited speed (9.6K to 76Kbps).
This transport protocol is unique to BACnet and can be utilized as either a master/slave network or a peer-to-peer network. It communicates at speeds up to 76Kbps over EIA-485 (twisted pair). This is the lowest cost solution for BACnet.

22. PTP Pros Cons Only choice for dial-up connections.
Special design for point-to-point applications.
Accommodates modern modem standards (V.32bis, V.42).
Cons
Transport media (point-to-point only; EIA 232).
Limited speed (9.6K to 56Kbps).
PTP is a transport protocol that is also unique to BACnet. It was developed to incorporate a method of dialed inter-network communications. It will support modern modem protocols, such as V.32bis and V.42, allowing communication at speeds of up to 56Kbps with compression over normal voice grade telephone lines.
PTP can also communicate over direct wired connections using EIA-232.
PTP is the format that the Simplex BACpac Portal communicates on.

23. LonTalk Pros Cons Scaleable speed (32K to 1.25Mbps).
Transport media (UTP, coax, RF, IR, fiberoptic).
Cons
Non-deterministic (contention based).
Distance limitations.
Single source chip (Motorola and Toshiba).
Need develop. tools.
Limited application size.
LonTalk allows scaleable speeds from 32K to 1.25Mbps and is comparable to MS/TP at the lower end and ARCNET at the higher end. It is the only transport protocol LAN that requires specific development tools. Motorola and Toshiba market the chips, but manufacture them in the same facility.
LonWorks is not BACnet. LonMark is not BACnet. LonTalk is not BACnet.
LonWorks is a proprietary network technology developed by Echelon Corporation that provides open control communications networks for a manufacturers product line. It enables the manufacturers to add local intelligence and communications capability to their products.
LonMark is the communication standard that provides guidelines for how to use the concepts of LonWorks.
LonTalk is a communication transport protocol that the LonWorks technology communicates on. BACnet characters can also travel along this transport protocol.

24. BACnet Transport Formats
higher
Ethernet
Cost
ARCNET
LonTalk
From this diagram it is shown that as performance increases, so does the cost of the LAN. It is also shown that in some instances there is quite a bit of overlap, where it may be possible to choose between 2 LAN technologies for the same requirements of cost and operation.
PTP is not shown on this diagram because it is specific for dialed up communications and cannot be compared to the other LAN technologies in this way trading off cost for performance.
MS/TP
faster
Speed

25. BACpac Portal BACnet compatible HVAC integration tested
NIST tested for compatibility
Building control integration tested
Pre-Tested to ASHRAE Updated Standards and UL Listed
Simplex has a BACnet gateway. The BACpac portal was introduced in April of It has been tested by Simplex and tested at NIST (National Institute for Science and Technology) for compatibility with the BACnet standard.
Simplex has also tested with other building control manufacturers, and we have pre-tested the BACpac portal to meet the most recent updated standards.

26. Simplex BACpac Portal (4190-9008)
BACpac Port A Port B
TB2-1 TX TB2-3 RX
TB2-2 RX TB2-1 TX
TB2-5 GND TB2-5 GND
BACpac Port A Port B
TB2-1 TX TB1-8 RX
TB2-2 RX TB1-6 TX
TB2-5 GND TB1-10 GND
Port Settings
Computer Port
9600 Baud
Even Parity
8 Bits
1 Stop Bit
The Simplex BACpac Portal.
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27. Simplex BACpac Portal BACnet Workstation PTP LAN Portal Portal Portal
(EIA 232)
(EIA 232)
PTP
(EIA 232)
Portal
Portal
EIA 232
EIA 232
Portal
50 ft Max.
50 ft Max.
Node
This is an interpretation of the unlimited communication between Simplex FACP (4100 and 4100U) and the 4120 Network and the BACnet Workstation when utilizing a PTP LAN.
As shown, the maximum distance the BACpac Portal may be from the FACP is 50 feet over EIA-232 (also known as Simplex RS232).
Node
EIA 232
Node
50 ft Max.
Node
GCC
4100
4100U

28. BACpac Portal on Ethernet LAN
HVAC
Panel
UUKL
Panel
Lighting
Panel
Control Panel
Control Panel
BACnet
Workstation
UUKL Panel
Ethernet
LAN
Ethernet
PTP to
Ethernet
If, for example, you were to interface to an existing college campus, chances are the LAN would be an Ethernet LAN. In this case, you would be required to have a Gateway which would translate the PTP protocol into Ethernet.
The BACpac Portal is responsible for converting the Fire Alarm information into BACnet Objects able to be transported per the PTP transport protocol. In order for the BACnet Workstation to be able to interpret this information, it would have to be converted from PTP to Ethernet via a Router. As show, the maximum distance the BACpac portal ma be from the FACP is 50 feet over EIA 232 (also known as Simplex RS232) and the maximum distance the Gateway may be from the BACpac Portal is 50 feet, also.
Control Panel
Control Panel
PTP
50 ft Max.
(EIA 232)
Portal
Vertical Lift
Panel
Security
Panel
4100U
EIA 232
50 ft Max.

29. Simplex... Offers BACnet interconnectivity
Unlocks the gateway barrier to proprietary building management networks
Reduces the cost of information exchange
In conclusion, Simplex is the first fire alarm manufacturer to apply BACnet interconnectivity to fire alarm systems.
Simplex fire systems are compatible with proprietary building management networks through BACnet, and we reduce the cost of information exchange with a standard agency listed BACnet gateway