BACNET

BACnet is an open communications protocol for building automation and control networks. The standards are controlled and/or referenced by ASHRAE, BACnet International, ANSI, and ISO.

BACnet has become the most popular protocol for building automation systems. The largest BACnet applications include systems and equipment used for heating, ventilating, and air-conditioning control, energy management lighting control, access control, and fire detection. It specifies mechanisms used by digital devices and building automation systems to exchange information and implement control algorithms.
BACnet Testing Laboratories was established by BACnet International to test products as per the BACnet standard and to support compliance testing and interoperability testing activities.

Many Veris products support BACnet MS/TP (over an RS-485 serial link) and some support BACnet IP (over Ethernet). The E50H2, E50H2A, E51H2 and E51H2A are certified by BTL for compliance with BACnet standards.

• • • BACnet MS/TP Client,

• • • BACnet MS/TP Server,

• • • BACnet/IP BBMD

• • • BACnet/IP Client,

• • • BACnet/IP Server,

Here is some more information about BACnet:

Protocol overview

The BACnet protocol defines a number of services that are used to communicate between building devices. The protocol services include Who-Is, I-Am, Who-Has, I-Have, which are used for Device and Object discovery. Services such as Read-Property and Write-Property are used for data sharing. The BACnet protocol defines a number of Objects that are acted upon by the services. The objects include Analog Input, Analog Output, Analog Value, Binary Input, Binary Output, Binary Value, Multi-State Input, Multi-State Output, Calendar, Event-Enrollment, File, Notification-Class, Group, Loop, Program, Schedule, Command, and Device.

BACnet objects

The standard 54 types of objects:

• • • Access Credential

• • • Access Door

• • • Access Point

• • • Access Rights

• • • Access User

• • • Access Zone

• • • Accumulator

• • • Alert Enrollment

• • • Analog Input: Sensor input

• • • Analog Output: Control output

• • • Analog Value: Setpoint or other analog control system parameter

• • • Averaging

• • • Binary Input: Switch input

• • • Binary Output: Relay output

• • • Binary Value: Control system parameter

• • • Bit String Value

• • • Calendar: A list of dates, such as holidays or special events, for scheduling

• • • Channel Object

• • • Character String Value

• • • Command: Writes multiple values to multiple objects in multiple devices to accomplish a specific purpose, such as day-mode to night-mode, or emergency mode

• • • Credential Data Input

• • • Date Pattern Value

• • • Date Value

• • • Date Time Pattern Value

• • • Date Time Value

• • • Device: Properties tell what objects and services the device supports, and other device-specific information such as vendor, firmware revision, etc.

• • • Event Enrollment: Describes an event that might be an error condition (e.g., “Input out of range”) or an alarm that other devices to know about. It can directly tell one device or use a Notification Class object to tell multiple devices

• • • Event Log

• • • File: Allows read and write access to data files supported by the device

• • • Global Group

• • • Group: Provides access to multiple properties of multiple objects in a read single operation

• • • Integer Value

• • • Large Analog Value

• • • Life Safety Point

• • • Life Safety Zone

• • • Lighting Output: for lighting features such as blink warning, fade time, low/high trim etc.

• • • Load Control

• • • Loop: Provides standardized access to a “PID control loop”

• • • Multi-state Input: Represents the status of a multiple-state process, such as a refrigerator’s On, Off, and Defrost cycles

• • • Multi-state Output: Represents the desired state of a multiple-state process (such as It’s Time to Cool, It’s Cold Enough and it’s Time to Defrost)

• • • Multi-state Value

• • • Network Security

• • • Notification Class: Contains a list of devices to be informed if an Event Enrollment object determines that a warning or alarm message needs to be sent

• • • Notification Forwarder

• • • Octet String Value

• • • Positive Integer Value

• • • Program: Allows a program running in the device to be started, stopped, loaded and unloaded, and reports the present status of the program

• • • Pulse Converter

• • • Schedule: Defines a weekly schedule of operations (performed by writing to specified list of objects with exceptions such as holidays. Can use a Calendar object for the exceptions

• • • Structured-View

• • • Time Pattern Value

• • • Time Value

• • • Trend Log

• • • Trend Log Multiple

BACnet testing

BACnet Testing Laboratories was established by BACnet International to test products as per BACnet standard and support compliance testing and interoperability testing activities and consists of BTL Manager and the BTL-WG. The general activities of the BTL are:

• • • Publish the BTL Implementation Guidelines document

• • • Certifying the products as per BACnet guidelines

• • • Support the activities of the BTL-WG,

• • • Maintaining the BTL test packages for technical support for use of pre-testing

• • • Approves Testing Laboratories for BTL Testing