Project Name: VVT Open
Project Number: 1
VVT Open Specification
Date: 7/13/2017
PART 1: GENERAL
PART 2: PRODUCTS
2.0 Section Includes
2.1 Materials
2.2 Communication
2.3 Operator Interface
2.4 Controller Software
2.5 Controllers
2.6 Input and Output Interface
2.7 Power Supplies and Line Filtering
2.8 Auxiliary Control Devices
2.1 Materials
Use new products the manufacturer is currently manufacturing and selling for use in new installations. Do not
use this installation as a product test site unless explicitly approved in writing by Owner. Spare parts shall be
available for at least five years after completion of this contract.
2.2 Communication
A. Control products, communication media, connectors, repeaters, hubs, and routers shall comprise a
BACnet internetwork. Controller and operator interface communication shall conform to ANSI/ASHRAE
Standard 135-2004, BACnet.
B. Install new wiring and network devices as required to provide a complete and workable control network.
C. Use existing Ethernet backbone for network segments marked "existing" on project drawings.
D. Each controller shall have a communication port for temporary connection to a laptop computer or other
operator interface. Connection shall support memory downloads and other commissioning and
troubleshooting operations.
E. Internetwork operator interface and value passing shall be transparent to internetwork architecture.
1. An operator interface connected to a controller shall allow the operator to interface with each
internetwork controller as if directly connected. Controller information such as data, and status
shall be viewable and editable from each internetwork controller.
2. Inputs, outputs, and control variables used to integrate control strategies across multiple
controllers shall be readable by each controller on the internetwork. An authorized operator
shall be able to edit cross-controller links by typing a standard object address or by using a
point-and-click interface.
F. Controllers with real-time clocks shall use the BACnet Time Synchronization service. System shall
automatically synchronize system clocks daily from an operator-designated controller via the
internetwork. If applicable, system shall automatically adjust for daylight saving and standard time.
2.3 Operator Interface
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Project Name: VVT Open
Project Number: 1
VVT Open Specification
Date: 7/13/2017
A. Description. The control system shall be as shown and consist of a high-speed, peer-to-peer network of
DDC controllers and a stand alone web server operator interface. Depict each mechanical system and
building floor plan by a point-and-click graphic. A web server shall gather data from this system and
generate web pages accessible through a conventional web browser on each PC connected to the
network. Operators shall be able to perform all normal operator functions through the web browser
interface. Operators with sufficient access level shall have an ability to make changes to all system and
equipment graphics in the web server in addition to having full DDC system access to make
configuration changes to the control system. Any tools required for making graphic changes shall be
provided with web server.
B. Operator Interface. Furnish one Web server interface as shown on the system drawings. Operators shall
be able to access all necessary operational information in the DDC system via client computer utilizing
IE web browser. Client computer and IE web browsing software shall not be furnished under this
section.
1. Web server shall connect via the LAN and be able to simultaneously serve up controller
information to multiple operators connected via LAN with IE web browsers. Each client web
browser connected to server shall be able to access all system information.
2. Web server shall be compatible with Wireless Access Protocol (WAP) enabled cellular
telephone or personal digital assistant (PDA). The PDA/WAP interface may be text-based and
shall provide a summary of the most important data.
3. With the use of a remote SMTP email server the operators interface web server shall be able to
notify personnel of an alarm or record information about an alarm in the DDC system.
C. Web Server Hardware. Furnish one compact web server with Ethernet port for LAN or direct operator
client computer access. The web server shall be capable of communicating to the peer to peer DDC
controller network. Any required installation or commissioning software shall be pre-installed on the web
server. Installation or commissioning of the web server shall be done through a client computer with a
standard web browser.
D. Communication. Web server or workstation and controllers shall communicate using BACnet protocol.
Web server or workstation and control network backbone shall communicate using ISO 8802-3
(Ethernet) Data Link/Physical layer protocol and BACnet/IP addressing as specified in ANSI/ASHRAE
135-2004, BACnet Annex J.
E. Operator Functions. Operator interface shall allow each authorized operator to execute the following
functions as a minimum:
1. Log In and Log Out. System shall require user name and password to log in to operator
interface.
2. Point-and-click Navigation. Operator interface shall be graphically based and shall allow
operators to access graphics for equipment and geographic areas using point-and-click
navigation.
3. View and Adjust Equipment Properties. Operators shall be able to view controlled equipment
status and to adjust operating parameters such as set points, PID gains, on and off controls,
and sensor calibration.
4. View and Adjust Operating Schedules. Operators shall be able to view scheduled operating
hours of each schedulable piece of equipment on a weekly or monthly calendar-based graphical
schedule display, to select and adjust each schedule and time period, and to simultaneously
schedule related equipment. System shall clearly show exception schedules and holidays on
the schedule display.
5. View and Respond to Alarms. Operators shall be able to view a list of currently active system
alarms, to acknowledge each alarm, and to clear (delete) unneeded alarms. Remote users shall
be able to receive alarms via emails or cell phone text messages.
6. View and Configure Trends. Operators shall be able to view a trend graph of each trended point
and to edit graph configuration to display a specific time period or data range. Operator shall be
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VVT Open Specification
Date: 7/13/2017
able to create custom trend graphs to display on the same page data from multiple trended
points.
7. View and Configure Reports. Operators shall be able to run preconfigured reports, to view
report results, and to customize report configuration to show data of interest.
8. Manage Control System Hardware. Operators shall be able to view controller status, to restart
(reboot) each controller, and to download new control software to each controller.
9. Manage Operator Access. Typically, only a few operators are authorized to manage operator
access. Authorized operators shall be able to view a list of operators with system access and of
functions they can perform while logged in. Operators shall be able to add operators, to delete
operators, and to edit operator function authorization. Operator shall be able to authorize each
operator function separately.
B. System Software.
1. Operating System and required software. Web server operator interface shall be a self
contained web server without the need for any type of maintenance. Any required operating
system or software shall be factory loaded and maintenance free.
2. System Graphics. Operator interface shall be graphical and shall include at least one graphic
per piece of equipment or occupied zone, graphics for each chilled water and hot water system,
and graphics that summarize conditions on each floor of each building included in this contract.
Indicate thermal comfort on floor plan summary graphics using dynamic colors to represent
zone temperature relative to zone setpoint.
a. Functionality. Graphics shall allow operator to monitor system status, to view a
summary of the most important data for each controlled zone or piece of equipment, to
use point-and-click navigation between zones or equipment, and to edit setpoints and
other specified parameters.
b. Animation. Graphics shall be able to animate by displaying different image files for
changed object status.
c.
Alarm Indication. Indicate areas or equipment in an alarm condition using color or other
visual indicator.
d. Format. Graphics shall be saved in an industry-standard format such as BMP, JPEG,
PNG, or GIF. Web-based system graphics shall be viewable on browsers compatible
with World Wide Web Consortium browser standards. Web graphic format shall require
no plug-in (such as HTML and JavaScript) or shall only require widely available no-cost
plug-ins (such as Active-X and Macromedia Flash).
C. System Tools. System shall provide the following functionality to authorized operators as an integral part
of the operator interface or as stand-alone software programs. If furnished as part of the interface, the
tool shall be available from each workstation or web browser interface. If furnished as a stand-alone
program, software shall be installable on standard Windows compatible PCs with no limit on the number
of copies that can be installed under the system license.
1. Automatic System Database Configuration. Each web server shall store internally store a copy
of the current system database, including controller firmware and software. Stored database
shall be automatically updated with each system configuration or controller firmware or software
change.
2. Controller Memory Download. Operators shall be able to download memory from the system
database to each controller.
3. System Configuration. Operators shall be able to configure the system.
4. Online Help. Context-sensitive online help for each tool shall assist operators in operating and
editing the system.
5. Security. System shall require a user name and password to view, edit, add, or delete data.
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Date: 7/13/2017
a. Operator Access. Each user name and password combination shall define accessible
viewing, editing, adding, and deleting functions in each system application, editor, and
object.
b. Automatic Log Out. Automatically log out each operator if no keyboard or mouse activity
is detected. Operators shall be able to adjust automatic log out delay.
c.
Encrypted Security Data. Store system security data including operator passwords in an
encrypted format. System shall not display operator passwords.
6. System Diagnostics. System shall automatically monitor controller and I/O point operation.
System shall annunciate controller failure and I/O point locking (manual overriding to a fixed
value).
7. Alarm Processing. System input and status objects shall be configurable to alarm on departing
from and on returning to normal state. Operator shall be able to enable or disable each alarm
and to configure alarm limits, alarm limit differentials, alarm states, and alarm reactions for each
system object. Configure and enable alarm points as specified in Points List. Alarms shall be
BACnet alarm objects and shall use BACnet alarm services.
8. Alarm Messages. Alarm messages shall use an English language descriptor without acronyms
or mnemonics to describe alarm source, location, and nature.
9. Alarm Reactions. Operator shall be able to configure (by object) actions workstation or web
server shall initiate on receipt of each alarm. As a minimum, workstation or web server shall be
able to log, print, start programs, display messages, send e-mail, send page, and audibly
annunciate.
10. Alarm Maintenance. Operators shall be able to view system alarms and changes of state
chronologically, to acknowledge and delete alarms, and to archive closed alarms to the
workstation or web server from each workstation or web browser interface.
11. Trend Configuration. Operator shall be able to configure trend sample or change of value (COV)
interval, start time, and stop time for each system data object and shall be able to retrieve data
for use in spreadsheets and standard database programs. Controller shall sample and store
trend data and shall be able to archive data to the hard disk. Configure trends as specified in
Points List. Trends shall be BACnet trend objects.
12. Object and Property Status and Control. Operator shall be able to view, and to edit if applicable,
the status of each system object and property by menu, on graphics.
13. Reports and Logs. Operator shall be able to select, to modify, to create, and to print reports and
logs. Operator shall be able to store report data in a format accessible by standard spreadsheet
and word processing programs.
14. Standard Reports. Furnish the following standard system reports:
a. Reports shall be filtered based upon the selected equipment
b. Alarm Reports
c.
i.
Alarm Summary - Current alarms
ii.
Alarm Sources – List of equipment and associated alarm conditions
iii.
Alarm Actions – Configured alarm actions such as e-mail and alarm pop-up
Schedule Reports
i.
Effective Schedules – Displays effective schedules for each equipment
ii.
Schedule Instances – Displays all schedules entered
d. Security Reports – Maintains audit of all actions taken through user interface
e. Commissioning Reports – Provide equipment checkout status and notes
f.
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Equipment Reports – Provide reports showing trended points and available network
points
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Date: 7/13/2017
15. Custom Reports. Operator shall be able to create custom reports that retrieve data, including
archived trend data, from the system, that analyze data using common algebraic calculations,
and that present results in tabular or graphical format. Reports shall be launched from the
operator interface.
16. Graphics Generation. Graphically based tools and documentation shall allow Operator to edit
system graphics, to create graphics, and to integrate graphics into the system. Operator shall
be able to add analog and binary values, dynamic text, static text, and animation files to a
background graphic using a mouse.
17. Graphics Library. Complete library of standard HVAC equipment graphics shall include
equipment such as chillers, boilers, air handlers, terminals, fan coils, and unit ventilators. Library
shall include standard symbols for other equipment including fans, pumps, coils, valves, piping,
dampers, and ductwork. Library graphic file format shall be compatible with graphics generation
tools.
D. Portable Operator's Terminal. Provide all necessary software to configure an IBM-compatible laptop
computer for use as a Portable Operator's Terminal. Operator shall be able to connect configured
Terminal to the system network or directly to each controller for programming, setting up, and
troubleshooting.
E. Timed override reporting (i-Vu Plus only)
1. The DDC system shall track all push button timed override events during unoccupied periods.
The system shall store time of the override event and time duration for each override event.
2. Web server shall allow operators to create custom reports detailing timed override events.
Timed override reports shall allow the following options:
3. Minimum billing time. A minimum amount of time that each override event will last.
4. Billing rate. A monetary rate per hour or per minute of the override duration.
5. Exemption times. A defined block of time during each week that is exempt from detecting
override events.
6. Allowances. A dollar amount of override usage that is allowed per tenant and is given at no
charge. This allowance will be subtracted from the tenant’s total override usage.
F. Web services data exchange (i-Vu Plus only)
System shall support Web services data exchange with any other system that complies with XML
(extensible markup language) and SOAP (simple object access protocol) standards specified by the
Web Services Interoperability Organization (WS-I) Basic Profile 1.0 or higher. Web services support
shall as a minimum be provided at the workstation or web server level and shall enable data to be read
from or written to the DDC system.
1. System shall support Web services read data requests by retrieving requested trend data or
point values (I/O hardware points, analog value software points, or binary value software points)
from any system controller or from the trend history database.
2. System shall support Web services write data request to each analog and binary object that can
be edited through the system operator interface by downloading a numeric value to the
specified object.
3. For read or write requests, the system shall require user name and password authentication
and shall support SSL (Secure Socket Layer) or equivalent data encryption.
4. System shall support discovery through a Web services connection or shall provide a tool
available through the Operator Interface that will reveal the path/identifier needed to allow a
third party Web services device to read data from or write data to any object in the system
which supports this service.
2.4 Controller Software
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Project Number: 1
VVT Open Specification
Date: 7/13/2017
A. Building and energy management application software shall reside and operate in system controllers.
Applications shall be configurable through the operator workstation, web browser interface, or
engineering workstation.
B. Memory and System Time. All controllers shall have a Non-Volatile Memory providing indefinite storage
of application and configuration data. The system must have an ability to maintain time, and
automatically correct for daylight savings time and leap year adjustments. In the event of power failure
or user generated power cycle, all system components must automatically updated with current time
and date from a network Time Sync device. The controller shall also have the capability of changing
occupancy mode by reading a set of discrete, dry contacts controlled by an external time clock.
C. Stand alone capability. All controllers shall be capable of providing all control functions of the HVAC
system without the use of a computer. The controllers shall include the inherent capability to access the
system control selections as well as to monitor system performance by means of a communicating
network with a PC and EMS software program.
D. System Security.
1. For Web server operator interface security options See Paragraph 2.3.G.5 (Security).
2. Other hand held or wall mounted local interface device that allow configuration access shall be
password protected with minimum of two levels of security. Level one shall provide limited
access to controller operational parameters and level two shall provide full access to controller
operational and configuration parameters.
E. Scheduling. For Web server operator interface scheduling See Paragraph 2.3.E.4 (View and Adjust
Operating Schedules).
1. System shall provide the following schedule options as a minimum:
2. Weekly. Provide separate schedules for each day of the week. Each schedule shall be able to
include up to 5 occupied periods (5 start-stop pairs or 10 events).
3. Exception. Operator shall be able to designate an exception schedule for each of the next 365
days. After an exception schedule has executed, system shall discard and replace exception
schedule with standard schedule for that day of the week.
4. Holiday. Operator shall be able to define 24 special or holiday schedules of varying length on a
scheduling calendar that repeats each year.
F. Binary and Analog Alarms. See Paragraph 2.3.G.7 (Alarm Processing).
G. Alarm Reporting. See Paragraph 2.3.G.9 (Alarm Reactions).
H. Remote Communication. System shall automatically contact operator workstation or server on receipt of
critical alarms.
I.
Demand Limiting.
1. System shall monitor building power consumption from building power meter pulse generator
signals or from building feeder line watt transducer or current transformer.
2. When power consumption exceeds adjustable levels, system shall automatically adjust set
points, de-energize low-priority equipment, and take other programmatic actions to reduce
demand as specified in Sequence of Operations for HVAC Controls. When demand drops
below adjustable levels, system shall restore loads as specified.
3. The controller shall be capable of providing separate heating and cooling demand control
utilizing two independent demand inputs.
J.
Sequencing. Application software shall sequence chillers, boilers, and pumps as specified in Sequence
of Operations for HVAC Controls.
K. PID Control. System shall provide direct- and reverse-acting PID (proportional-integral-derivative)
algorithms. Each algorithm shall have anti-windup and selectable controlled variable, setpoint, and PID
gains. Each algorithm shall calculate a time-varying analog value that can be used to position an output
or to stage a series of outputs.
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L. Staggered Start. System shall stagger controlled equipment restart after power outage. Operator shall
be able to adjust equipment restart order and time delay between equipment restarts.
M. Anti-Short Cycling. Binary output objects shall be protected from short cycling by means of
preconfigured minimum on-time and off-time settings, customized for the specific requirements of the
application.
N. On and Off Control with Differential. System shall provide direct- and reverse-acting on and off
algorithms with adjustable differential to cycle a binary output based on a controlled variable and
setpoint.
O. Zoning system compatible with constant volume air source (Variable Volume/Variable Temperature)
(VVT). The zoning system shall be compatible with constant volume air source and consist of
programmable, multiple communicating Zone Controllers and a Bypass Controller. The system shall
also include a complete array of input and output devices. The system shall provide full control of HVAC
heating and cooling equipment in a multiple zone application. The zoning system shall be capable of
operating as a stand-alone system or networked with multiple systems to communicating air source
controllers.
1. Zone control. Each zone shall be capable of monitoring space conditions and providing the
correct amount of conditioned air to satisfy the space load. Each zone shall be capable of the
following:
a. Space temperatures control. To maintain individual heating and cooling set points.
b. Relative Humidity/Air Quality (DCV). Each zone shall be capable of maintaining space
relative humidity set point or air quality set point (zone level demand control ventilation)
as defined in ASHRAE 62-1989 (including Addendum 62a-1990).
c.
Demand coordination. Each zone shall be capable of zone demand data coordination
with other zones in the system.
2. Static pressure control. The zoning system shall be capable of maintaining a user adjustable
supply air duct static pressure set point.
a. The Bypass controller shall additionally provide the capability to increase system airflow
during conditions when the temperature of the supply air from the equipment is
approaching the limits of operation. In these cases, the Bypass controller shall raise the
static pressure setpoint to a user configurable maximum limit in order to increase the
system airflow during these conditions.
b. The Bypass control shall contain the ability to monitor the bypass damper movement (or
VFD speed) and automatically adjust the setpoint control band and/or hysteresis in
order to provide stability and prevent premature actuator failure.
3. Air source control. Shall control all associated HVAC rooftop equipment functions, and be
capable of stand-alone or networked operation. The resident algorithms shall use error
reduction logic as designated in ASHRAE standard 90.1 to provide temperature control and
lower energy usage. The Air source shall be capable of zone demand data coordination with the
associated zones.
4. System Terminal Modes. Each air terminal mode shall be based on the current air source
mode, terminal type, space temperature, and the current temperature set points.
a. Off:
i. All terminal dampers will maintain a 65% open position. Fans shall be disabled.
ii. If the zone requirement is heating, all single duct terminals shall maintain their
damper position at 65%. Any zone controller servicing a parallel box shall fully
close their dampers while the fan is operating. If local heat is available, the
parallel fans shall start and local heat shall be enabled to maintain its unoccupied
heating set point. The damper shall be modulated open to 65% after heating is no
longer required.
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b. Cooling and Night Time Free Cooling (NTFC):
i. If the zone requirement is none, then the zone controllers shall modulate their
dampers to maintain their minimum cooling damper position or damper ventilation
position if the supply air temp is between 65 and 75 F. During the NTFC mode
the zone controller shall control between its occupied heating and cooling set
points. During the cooling mode, the zone controller shall modulate its damper to
its appropriate (occupied or unoccupied) cooling set point.
ii. If the zone requirement is cooling, then the zone controllers shall modulate their
air dampers between their minimum and maximum cooling damper position to
maintain their cooling set point. Parallel fans shall be disabled unless the damper
has closed below the user adjustable fan-on minimum position (optional). In that
case, the fan shall be energized to mix return air with the cold primary air in order
to prevent “cold air dumping” from the diffusers.
iii. If the zone requirement is heating, then the zone controllers shall modulate their
dampers to maintain their minimum cooling damper position. Any zone controllers
servicing single duct units with reheat capability shall maintain the greater of
either the minimum cooling damper position or the specified reheat damper
position. Zone controllers servicing parallel units shall enable their fans while the
damper shall maintain its minimum cooling damper position.
c.
Vent:
i. If the air source equipment is operating in a fan only mode to provide ventilation
without mechanical heating or cooling, then the zone controllers shall maintain
the user configured ventilation damper position.
d. Heat:
i. If the zone requirement is none, then the zone controller shall maintain its
minimum heating damper position. Parallel fans shall be disabled and their air
damper shall be modulated to maintain their minimum heating damper position.
ii. If the zone requirement is cooling, then the zone controller shall modulate its
damper to maintain its minimum heating damper position. Parallel fans shall be
disabled.
iii. If the zone requirement is heating, then the zone controllers shall modulate their
air dampers between their minimum and maximum heating damper position to
maintain their heating set point.
e. Pressurization:
i. If the zone requirement is none or cooling, then the zone controller shall maintain
its maximum cooling damper position. Parallel fans shall be disabled.
ii. If the zone requirement is heating, and the zone controller has been enabled to
provide local heating, then the zone controller shall modulate its damper to its
maximum cooling damper position and enable its auxiliary heat. If local heat is
not available, the damper shall still be modulated to maintain its maximum cooling
damper position.
f.
Evacuation:
i. During the Evacuation mode all terminal fans shall be disabled and all dampers
shall close.
5. Air source interface. The zoning system shall be capable of zone demand data coordination
with a communicating rooftop. Setpoint and zone temperature information from the zones shall
be shared with the rooftop controller so that the rooftop controller’s error reduction calculations
can determine the proper number of heating or cooling stages to operate in order to satisfy the
system load.
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a. The zoning system shall have the capability of linking up to 32 zones to a single air
source and determining system heating and cooling requirements.
b. The zoning system shall be capable of providing a communication check of all
associated controls and display device type as well as error conditions.
c.
The zoning system shall coordinate and exchange the flowing data as minimum:
i. Average zone temperature
ii. Average occupied zone temperature
iii. Average occupied and unoccupied heat/cool set points
iv. Occupancy status
d. Space temperature and space temperature set points for use by the air source
controller shall include a weighted factor, proportional to the size of the zone.
e. Only those zones with valid temperature readings shall be included.
f.
The zoning system shall provide periodic updates to the air source.
g. The zoning system shall obtain and support the following air source modes as a
minimum:
i. Off
ii. Cooling
iii. Heating
iv. Night Time Free Cooling
v. Ventilation
vi. Pressurization
vii. Evacuation
h. The air source controller shall, through the Air Distribution System, bias its occupancy
time schedules to provide optimization routines and occupant override.
i.
For those zoning systems that do not include inherent air source interface capacity,
each zone shall independently determine the operational mode of the equipment
through its associated duct temperature sensor mounted in the supply ductwork. If there
is air source controller, then the system will assumed to be always On.
6. HVAC Equipment Protection. The air sources controller shall be capable of monitoring the
leaving air temperature to control stages in both the heating and cooling modes. It shall have
the capability to shut down stages based on a rise or fall in leaving air temperature above or
below adjustable or calculated values. Calculated supply air temperature requirements shall be
based on error reduction calculations from reference zone data to determine the optimum
supply air temperature to satisfy space requirements. The system shall provide protection from
short cycling of heating and cooling by utilizing time guards and minimum run time
configurations.
7. Energy Conservation.
a. Load balancing from error reduction calculations that optimize staging.
b. The locking out of mechanical heating or cooling modes based on configurable outside
air temperature limits.
c.
Staggered start. The system shall intelligently start all equipment in a stagger start
manner after a transition from unoccupied to occupied modes as well as power failure
to reduce high peak power consumption on start-up.
d. Peak Demand Limiting. Controllers in the system shall have the capability of being
overridden by separate heating and cooling Peak Demand Limiting signals.
Option/General purpose controller existing on the communications bus shall be able to
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send a demand limiting broadcast to reduce overall energy consumption and control on
and off peak time kW usage
e. Temperature compensated start. The zone controller shall be capable of supporting
temperature compensated start with the air source. Prior to occupancy the zone
controllers and Air Source shall work together to provide zone-by-zone temperature
compensated conditioning. The air source will track the time required for recovery
report the optimal start bias time to the zones prior to each occupied period so that the
zone can start conditioning the space prior to occupancy.
8. Demand Control Ventilation (DCV). The zone shall be capable of reading an analog signal from
a CO2 sensor or other sensor measuring volatile contaminants, or relative humidity and provide
DCV at the zone by calculating a DCV damper position and participate in system DCV operation
with the air source
a. System DCV (System Level).The zoning system shall have the ability to collect the
DCV value from any or all of the zone controllers in the system. These values may be
the average or the highest sensor value which will be transmitted to an air source
controller’s analog DCV sensor input. The air sources configured DCV routine may
perform the appropriate actions to reduce CO2 concentration at the reporting zones.
The system shall be capable of maintaining a ventilation setpoint through a DCV
algorithm in conjunction with zone to fulfill the requirements of ASHRAE standard, 621989 “Ventilation For Acceptable Indoor Air Quality” (including Addendum 62a-1990)..
b. Local DCV (Zone Level). Each zone shall be capable of reading an analog signal from a
CO2 sensor or other sensors measuring volatile contaminants and maintaining a
ventilation setpoint through a DCV algorithm in conjunction with system controller to
fulfill the requirements of ASHRAE standard, 62-1989 “Ventilation For Acceptable
Indoor Air Quality” (including Addendum 62a-1990). The zone shall calculate a DCV
damper position for the zone based on an error reduction calculation. When the DCV
damper position value is greater than temperature control damper position the DCV
damper position shall be used to position the damper. System heating and cooling and
zone supplemental heat shall be allowed to operate.
9. Abnormal Conditions. The proposed system shall include the ability to detect abnormal
conditions, and to react to them automatically. A return to normal conditions shall also generate
a return to normal notification and the system shall revert back to its original control scheme
before the abnormal condition existed. The following abnormal terminal conditions shall
automatically generate an alarm and the system shall take the following actions:
a. If a space temperature sensor is determined by the zone controller to be invalid, the
zone controller shall generate an alarm. During this condition, the zone damper will be
positioned to either the minimum heating, minimum cooling or the configured ventilation
damper position, based on the air source equipment operating mode.
b. If a relative humidity sensor is determined by the zone controller to be invalid, the zone
controller shall generate an alarm.
c.
If an indoor air quality sensor is determined by the zone controller to be invalid, the
zone controller shall generate an alarm, and disable its IAQ algorithm.
d. System level demand coordination. If an air source controller is participating in demand
coordination with other zones and loses communication with the associated zones, it
shall generate an alarm. Likewise, any zone detecting a communication failure, will
generate an alarm.
e. Zone level demand coordination. If the system looses communication with one of the
zones associated with that system the zoning system shall remove that zone
temperature from its weighted averages. The zone controller shall continue to operate
in a stand-alone mode.
f.
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If the zoning system if configured to interface with the air source for zone demand data
coordination and that communication is broken, each zone controller shall determine
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the equipment operating mode based on the temperature of the primary air. The air
source will be assumed to be always on.
2.5 Controllers
A. General. The control system shall be available as a complete package with the required input sensors
and devices readily available. Provide Building Controllers (BC), Advanced Application Controllers
(AAC), Application Specific Controllers (ASC), and Sensors (SEN) as required to achieve performance
specified in Paragraph 2.4.
B. Every device in the system which executes control logic and directly controls HVAC equipment must
conform to a standard BACnet Device profile as specified in ANSI/ASHRAE 135-2004, BACnet Annex
L. Unless otherwise specified.
C. BACnet.
1. Building Controllers (BCs). Each BC shall conform to BACnet Building Controller (B-BC) device
profile as specified in ANSI/ASHRAE 135-2004, BACnet Annex L and shall be listed as a
certified B-BC in the BACnet Testing Laboratories (BTL) Product Listing.
2. Advanced Application Controllers (AACs). Each AAC shall conform to BACnet Advanced
Application Controller (B-AAC) device profile as specified in ANSI/ASHRAE 135-2004, BACnet
Annex L and shall be listed as a certified B-AAC in the BACnet Testing Laboratories (BTL)
Product Listing.
3. Application Specific Controllers (ASCs). Each ASC shall conform to BACnet Application Specific
Controller (B-ASC) device profile as specified in ANSI/ASHRAE 135-2004, BACnet Annex L
and shall be listed as a certified B-ASC in the BACnet Testing Laboratories (BTL) Product
Listing.
4. BACnet Communication.
a. Each BC shall reside on or be connected to a BACnet network using ISO 8802-3
(Ethernet) Data Link/Physical layer protocol and BACnet/IP addressing.
b. BACnet routing shall be performed by BCs or other BACnet device routers as
necessary to connect BCs to networks of AACs and ASCs.
c.
Each AAC shall reside on a BACnet network using ISO 8802-3 (Ethernet) Data
Link/Physical layer protocol with BACnet/IP addressing, or it shall reside on a BACnet
network using the MS/TP Data Link/Physical layer protocol.
d. Each ASC shall reside on a BACnet network using the MS/TP Data Link/Physical layer
protocol.
D. Communication.
1. Service Port. Each controller shall provide a service communication port for connection to a
Portable Operator's Terminal. Connection shall be extended to space temperature sensor ports
where shown on drawings.
2. Signal Management. BC and ASC operating systems shall manage input and output
communication signals to allow distributed controllers to share real and virtual object information
and to allow for central monitoring and alarms.
3. Data Sharing. Each BC and AAC shall share data as required with each networked BC and
AAC.
4. Stand-Alone Operation. Each piece of equipment shall be controlled by a single controller to
provide stand-alone control in the event of communication failure. All I/O points specified for a
piece of equipment shall be integral to its controller. Provide stable and reliable stand-alone
control using default values or other method for values normally read over the network.
E. Environment. Controller hardware shall be suitable for anticipated ambient conditions.
1. Controllers used outdoors or in wet ambient conditions shall be mounted in waterproof
enclosures and shall be rated for operation at -29°C to 60°C (-20°F to 140°F).
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2. Controllers used in conditioned space shall be mounted in dust-protective enclosures and shall
be rated for operation at 0°C to 50°C (32°F to 120°F).
F. Keypad. Where specified provide a local keypad and display for each BC and ASC. Operator shall be
able to use keypad to view and edit data. Keypad and display shall require password to prevent
unauthorized use. If the manufacturer does not normally provide a keypad and display for each BC and
ASC, provide the software and any interface cabling needed to use a laptop computer as a Portable
Operator's Terminal for the system.
G. Serviceability.
1. Controllers shall have diagnostic LEDs for power, communication, and processor.
2. Wires shall be connected to a field-removable modular terminal strip or to a termination card
connected by a ribbon cable.
3. All controllers in the system shall continually check its processor and memory circuit status and
shall generate an alarm on abnormal operation. System shall continuously check controller
network and generate alarm for each controller that fails to respond.
H. Memory.
1. Controller memory shall support operating system, database, and programming requirements.
2. Each controller in the system shall use nonvolatile memory providing indefinite storage of BIOS,
application programming, and all configuration data in the event of power loss.
I.
Immunity to Power and Noise. Controllers shall be able to operate at 90% to 110% of nominal voltage
rating and shall perform an orderly shutdown below 80% nominal voltage. Operation shall be protected
against electrical noise of 5 to 120 Hz and from keyed radios up to 5 W at 1 m (3 ft).
J.
Zone Controller (ZC). Defined as Application Specific Controllers (ASC) shall be capable of independent
zone control or function as part of the zoning system to achieve performance as specified for zone
control in Paragraph 2.4.
1. Input and output devices shall be wired to “quick-connect plug type” terminals to facilitate
removal of the module without disconnecting wiring from the plug type terminal.
2. ZC shall have an integrated brushless actuator and be capable of operating zone dampers as
well as parallel fan powered terminal boxes.
3. ZC shall be capable of controlling supplemental heat or auxiliary heat sources, including fan
control, when required at the zone level.
4. The zone controller shall have the capability to support adjustable minimum and maximum
damper positions.
5. ZC shall be capable of reading an analog signal from a CO2 sensor or other sensor measuring
volatile contaminants, or relative humidity and provide DCV at the zone by calculating a DCV
damper position and participate in system DCV operation with the air source.
K. Bypass Controller. Defined as Application Specific Controllers (ASC) shall be capable of reading supply
static pressure and controlling the bypass damper (or a VFD speed control output) to maintain the
supply static set point. This operation shall be provided when operating within a zoning system
application, as specified for bypass control in Paragraph 2.4 or in a stand-alone mode.
1. Input and output devices shall be wired to “quick-connect plug type” terminals to facilitate
removal of the module without disconnecting wiring from the plug type terminal.
2. The controller shall contain an onboard pressure sensor to measure duct static pressure. The
sensor measuring range shall be from 0.0 to 2.0 inches H2O.
3. Bypass Controller shall have an integrated brushless actuator providing a minimum of 35 in/lbs
of torque and be capable of operating a bypass damper. The direction of rotation shall be
reversible in the field to accommodate field supplied bypass damper assemblies.
4. Bypass Controller shall provide an analog output signal for an external actuator or to control the
speed of a variable frequency drive (VFD).
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L. Rooftop Unit Controller (RTC). Defined as Application Specific Controllers (ASC), shall control all
associated HVAC Constant Volume rooftop equipment functions, this operation shall be provided when
operating within a zoning system application, as specified for an air source control, in Paragraph 2.4 or
in a stand-alone mode. The resident algorithms shall use error reduction logic as designated in
ASHRAE standard 90.1 to provide temperature control and energy usage.
1. Capacity control shall be based on the use of a conventional thermostat, or programmable
thermostat, or alternatively, a constant volume unit may utilize its own internal time clock and
setpoints (cooling and heating) coupled with a room (wired or network communicating) sensor
for capacity control. The controls shall provide separate occupied and unoccupied cooling and
heating setpoints – except if a conventional thermostat is used.
2. RTC shall feature and maintain a 365-day Real-Time Clock/Calendar with holiday functions.
3. RTC shall be capable of stand-alone or networked operation.
4. In the stand alone mode, each RTC shall establish occupancy scheduling based on its own
local occupancy schedule, the closure of a contact connected to an external time clock or EMS
system, or by a timed override request (1 to 24 hours) through its space temperature sensor
override button.
5. When networked, RTC occupancy may be established by user interface or occupancy signal
from other controller located in network.
6. RTC shall utilize fan control, 2 stages of cooling, and up to 3 stages of heating to maintain zone
temperature at setpoint.
7. RTC shall provide analog output signal for economizer control.
M. Water Source Heat Pump Controller (WSHPC). Defined as Application Specific Controllers (ASC) shall
consist of a factory-installed solid-state microprocessor circuit board, transformers, associated control
hardware, and control software. WSHPC shall control all associated HVAC water source heat pump
equipment functions, this operation shall be provided when operating within a zoning system
application, as specified for an air source control, in Paragraph 2.4 or in a stand-alone mode.
1. WSHP shall feature and maintain a 365-day Real-Time Clock/Calendar with holiday functions.
2. The WSHPC shall be capable of stand-alone or networked operation.
3. In the stand alone mode, each WSHPC shall establish occupancy scheduling based on its own
local occupancy schedule, the closure of a contact connected to an external time clock or EMS
system, or by a timed override request (1 to 24 hours) through its space temperature sensor
override button.
4. When networked, WSHP occupancy may be established by user interface or occupancy signal
from other controller located in network.
5. The software shall control a one, two or three speed supply fan, up to 2 stages of compression
for cooling and heating, and a reversing valve with either B or O type control.
6. The controller shall be capable of controlling a field supplied auxiliary heating coil, either
electric, modulating water/steam, or two position water/steam, to provide supplemental heating
capability.
7. The controller shall provide the capability to control either a factory or field supplied water
economizer coil mounted in the return air inlet and connected to the condenser water loop in
order to utilize the condenser water loop to reduce energy consumption.
8. The controller shall provide a condensate monitoring function that shall disable the unit prior to
a condensate overflow condition occurring and also generate an alarm to notify of the condition.
9. Alarm/Alert Processing - The WSHPC shall be shipped with factory default alarm thresholds
and time delays and contain routine(s) to process alarms and alerts. All alarms/alerts shall be
displayed at a local Interface device, portable PC, and via the network to a remote EMS
operator’s station.
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10. Factory Supplied. The following control hardware shall be factory-supplied and installed unless
noted otherwise below:
a. Leaving Water Temperature Sensor
b. Supply Air Sensor
c.
Condensate overflow detection device
d. Indoor Air Fan, Cooling, and Heating Stages relays
e. Remote Device Inputs: WSHPC shall be started/stopped based on this dry contact
position
11. Field supplied and installed devices. The installer shall provide one or more of the following
sensors as shown on the plans:
a. Compatible Space Temperature Sensor. The space temperature sensor shall be fieldsupplied for field installation as shown on the plans. The sensor shall contain:
i. If required remote occupant override button
ii. Remote communication port
iii. If required a setpoint adjustment.
iv. If required LCD display.
b. Indoor Air Quality (IAQ) Sensor: The filed-supplied and field-mounted and wired sensor
utilize an infrared diffusion sampling tube with a range of 0 to 2000 PPM and shall
include indicating LED’s.
N. General Purpose Controller. Defined as Advanced Application Controllers (AAC) the General Purpose
Controller shall be a solid state micro-controller with pre-tested and factory configured software
designed for controlling building equipment using DDC algorithms and facility management routines.
The controller shall be capable of operating in either a stand-alone mode or as part of a network.
1. Input and output devices shall be wired to “quick-connect plug type” terminals to facilitate
removal of the module without disconnecting wiring from the plug type terminal.
2. Inputs. Shall support the following input types as a minimum
a. Dry or pulsed dry contacts
b. 0-5 VDC
c.
0–10 VDC
d. 4–20 mA
e. 10K thermistors
f.
1000-ohm Nickel RTD
3. Outputs. Shall support the following input types as a minimum
a. Discrete types
b. 0–10 VDC analog type
c.
4–20 mA analog type
4. Real-Time Clock. Shall feature and maintain a 365-day hardware clock/calendar with holiday
functions.
5. Direct digital control routines. The following types of direct digital control routines shall be
provided as a minimum:
a. Indoor/Outdoor Lighting Control
b. Time Schedule with/without override
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Enthalpy/Analog Comparison
d. Analog Comparison
e. Interlock / Permissive Interlock
f.
Fan Control
g. Time Schedule with/without override
h. Unit Heater
i.
Constant Volume Air Source control
j.
WSHP Loop Monitor and Pump Control
k.
WSHP Loop Cooling – Closed Circuit Tower
l.
WSHP Loop Cooling – Open Circuit Tower
m. WSHP Loop Heating
n. Electric Meter with Demand Limit
2.6 Input and Output Interface
A. General. Hard-wire input and output points to BCs, AACs, or ASCs.
B. Protection. Shorting an input or output point to itself, to another point, or to ground shall cause no
controller damage. Input or output point contact with up to 24 V for any duration shall cause no
controller damage.
C. Binary Inputs. Binary inputs shall monitor the on and off signal from a remote device. Binary inputs shall
provide a wetting current of at least 12 mA and shall be protected against contact bounce and noise.
Binary inputs shall sense dry contact closure without application of power external to the controller.
D. Pulse Accumulation Inputs. Pulse accumulation inputs shall conform to binary input requirements and
shall accumulate up to 10 pulses per second.
E. Analog Inputs. Analog inputs shall monitor low-voltage (0-10 Vdc), current (4-20 mA), or resistance
(thermistor or RTD) signals. Analog inputs shall be compatible with and field configurable to commonly
available sensing devices.
F. Binary Outputs. Binary outputs shall send an on-or-off signal for on and off control. Building Controller
binary outputs shall have three-position (on-off-auto) override switches and status lights. Outputs shall
be selectable for normally open or normally closed operation.
G. Analog Outputs. Analog outputs shall send a modulating 0-10 Vdc or 4-20 mA signal as required to
properly control output devices. Each Building Controller analog output shall have a two-position (automanual) switch, a manually adjustable potentiometer, and status lights. Analog outputs shall not drift
more than 0.4% of range annually.
H. Universal Inputs and Outputs. Inputs and outputs that can be designated as either binary or analog in
software shall conform to the provisions of this section that are appropriate for their designated use.
2.7 Power Supplies And Line Filtering
A. Power Supplies. Control transformers shall be UL listed. Furnish Class 2 current-limiting type or furnish
over-current protection in primary and secondary circuits for Class 2 service in accordance with NEC
requirements. Limit connected loads to 80% of rated capacity.
1. DC power supply output shall match output current and voltage requirements. Unit shall be fullwave rectifier type with output ripple of 5.0 mV maximum peak-to-peak. Regulation shall be
1.0% line and load combined, with 100-microsecond response time for 50% load changes. Unit
shall have built-in over-voltage and over-current protection and shall be able to withstand 150%
current overload for at least three seconds without trip-out or failure.
a. Unit shall operate between 0°C and 50°C (32°F and 120°F). EM/RF shall meet FCC
Class B and VDE 0871 for Class B and MILSTD 810C for shock and vibration.
b. Line voltage units shall be UL recognized and CSA listed.
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B. Power Line Filtering.
1. Provide internal or external transient voltage and surge suppression for workstations and
controllers. Surge protection shall have:
2. Dielectric strength of 1000 V minimum
3. Response time of 10 nanoseconds or less
4. Transverse mode noise attenuation of 65 dB or greater
5. Common mode noise attenuation of 150 dB or greater at 40-100 Hz
2.8 Auxiliary Control Devices
A. Zone Dampers. Each Zone Damper shall include:
1. A motorized damper assembly constructed of 24 gage galvanized iron with blade of 20 gage.
2. Blade operation providing full modulation from open to closed position.
3. The ability to operate in a controlling/link arrangement, where the controlling damper is operated
by the zone controller. The zone controller shall provide a separate 0-10 vdc output proportional
to the controlling damper position (available only if no modulating heat is used) to be used to
link additional zone dampers. These additional dampers will track the position of the controlling
damper and modulate to the same position as the controlling damper. The number of additional
dampers are dependent upon the load of each field supplied damper actuator and the external
output drive capability.
4. Round dampers shall have elliptical blades with a seal around the entire damper blade edge.
Rectangular dampers shall have fully sealed edges.
5. A duct temperature sensor shall be an integral part of the damper assembly.
B. Ventilation Sensors Wall-Mounted Carbon Dioxide Sensors. Carbon dioxide sensor (CO2) shall have
integral programming to perform automatic baseline calibration without user interface. The
recommended manual recalibration period shall not be less than five years. Sensors shall be equipped
with an LED display. Other features of wall-mounted Carbon Dioxide sensors shall include:
1. Operating conditions: 60 to 90ºF (15 to 32ºC), and 0 to 95% RH, non-condensing
2. Power supply: 18-30 VAC, 50/60 Hz half-wave rectified [18-–42 VDC polarity protected]
3. CO2 sensor output: 4 to 20 mA or 0 to 10-volt signal.
4. CO2 measurement range: 0–2,000 PPM.
5. Setpoint: adjustable.
6. Sensitivity: ±20 PPM.
7. Accuracy: ±100 PPM at 60 to 90ºF (15 to 32ºC); and 760 mmHg
C. Ventilation Sensors Duct-Mounted Carbon Dioxide Sensor.
1. Carbon Dioxide (CO2) sensors for duct-mounted applications shall be identical to the wallmounted sensors specified above except as described below.
2. The CO2 sensor shall be mounted in an enclosed aspirator box that mounts directly to the duct.
The aspirator box shall be equipped with an induction tube to direct a side-stream of air from the
duct through the CO2 sensor. A hinged, clear access door shall be installed on the front of the
aspirator box to permit access to the sensor and to permit viewing the sensor without opening
the door.
3. CO2 sensors for duct-mounted applications shall be designed for flow-through sampling.
D. Temperature Sensors.
1. Type. Temperature sensors shall be nominal 10K ohm thermistor type.
2. Duct Sensors. Duct sensors shall be single point or averaging as shown. Averaging sensors
shall be a minimum of 1.5 m (5 ft) in length per 1 m 2(10 ft 2) of duct cross-section.
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3. Space Sensors. Space sensors shall have setpoint adjustment, override switch, display, and
communication port as shown.
E. Humidity Sensors.
1. Duct and room sensors shall have a sensing range of 20%-80%.
2. Duct sensors shall have a sampling chamber.
3. Outdoor air humidity sensors shall have a sensing range of 20%-95% RH and shall be suitable
for ambient conditions of 40°C-75°C (-40°F-170°F).
4. Humidity sensors shall not drift more than 1% of full scale annually.
F. Voltage Transformers.
1. AC voltage transformers shall be UL/CSA recognized, 600 Vac rated, and shall have built-in
fuse protection.
2. Transformers shall be suitable for ambient temperatures of 4°C-55°C (40°F-130°F) and shall
provide ±0.5% accuracy at 24 Vac and 5 VA load.
3. Windings (except for terminals) shall be completely enclosed with metal or plastic.
PART 3: EXECUTION
Sequence of Operations for HVAC Controls
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APPENDIX A: Glossary of Terms
Terms used within the Specification Text:

Advanced Application Controller (AAC):
A configurable control module with pre-tested and factory configured software specifically designed for
regulating building equipment using closed-loop Direct Digital Control and facility management routines.
This control module may be capable of some of the advanced features found in Building Controllers
(storing trends, initiating read and write requests, etc.) but it does not serve as a master controller.

Application Specific Controller (ASC):
A pre-programmed control module which is intended for use in a specific application. ASCs may be
configurable, in that the user can choose between various pre-programmed options, but it does not
support full custom programming. ASCs are often used on terminal equipment such as VAV/VVT boxes
or fan coil units. In many vendors' architectures ASCs do not store trends or schedules but instead rely
upon a Building Controller to provide those functions.

BACnet/IP:
An approved BACnet network type which uses an Ethernet carrier and IP addressing.

BACnet MS/TP:
An approved BACnet network type which uses a Master-Slave Token Passing configuration. MS/TP
networks are unique to BACnet and utilize EIA485 twisted pair topology running at 9600 to 76,800 bps.

Building Controller (BC):
A control module which is capable of serving as a router to devices on a subnet, and initiating read and
write requests to other controllers. Typically this controller is located on the Ethernet/IP backbone of the
BAS.

Direct Digital Control (DDC):
A control system in which a digital computer or microprocessor is directly connected to the valves,
dampers, and other actuators which control the system, as opposed to indirectly controlling a system by
resetting setpoints on an electronic controller.

PICS - Protocol Implementation Conformance Statement:
A written document, created by the manufacturer of a device, which identifies the particular options
specified by BACnet that are implemented in the device.

Web services:
Web services are a standard method of exchanging data between computer systems using the XML
(extensible markup language) and SOAP (simple object access protocol) standards. Web services can
be used at any level within a Building Automation System (BAS), but most commonly they are used to
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transfer data between BAS using different protocols or between a BAS and a non-BAS system such as
a tenant billing system or a utility management system.
Terms used within the Sequences of Operation:

adj.
Adjustable by the end user, through the supplied user interface.

AI, AO, etc. (Column Headings on Points List)
AI = Analog Input. A physical input to the control module.
AO = Analog Output. A physical output from the control module.
AV = Analog Value. An intermediate (software) point that may be editable or read-only. Editable AVs
are typically used to allow the user to set a fixed control parameter, such as a setpoint. Read Only AVs
are typically used to display the status of a control operation.
BI = Binary Input. A physical input to the control module.
BO = Binary Output. A physical output from the control module.
BV = Binary Value. An intermediate (software) point that may be editable or read-only. Editable BVs are
typically used to allow the user to set a fixed control parameter, such as a setpoint. Read Only BVs are
typically used to display the status of a control operation.
Sched = Schedule. The control algorithm for this equipment shall include a user editable schedule.
Trend. The control system shall be configured to collect and display a trend log of this object. The
trending interval shall be no less than one sample every 5 minutes. (Change of Value trending, where a
sample is taken every time the value changes by more than a user-defined minimum, is an acceptable
alternative.)
Alarm. The control system shall be configured to generate an alarm when this object exceeds user
definable limits, as described in the Sequence of Controls.
Note: If the specifications require use of the BACnet protocol, all of the above shall be provided as
BACnet objects.

KW Demand Limiting:
An energy management strategy that reduces energy consumption when a system's electric power
meter exceeds an operator-defined threshold.
When power consumption exceeds defined levels, the system automatically adjust setpoints, deenergizes low priority equipment, and takes other pre-programmed actions to avoid peak demand
charges. As the demand drops, the system restores loads in a predetermined manner.

Occupant Override Switch, or Timed Local Override:
A control option that allows building occupants to override the programmed HVAC schedule for a limited
period of time.
When the override time expires, the zone returns to its unoccupied state.

Occupant Setpoint Adjustment:
A control option that allows building occupants to adjust - within limits set by the HVAC control system the heating and cooling setpoints of selected zones. Typically the user interface for this function is built
into the zone sensor.
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Optimal Start-Up:
A control strategy that automatically starts an HVAC system at the latest possible time yet ensures
comfort conditions by the time the building becomes occupied.
In a typical implementation, a controller measures the temperature of the zone and the outside air.
Then, using design heating or cooling capacity at the design outside air temperature, the system
computes how long a unit must run at maximum capacity to bring the zone temperature to its occupied
setpoint.
Contracting Terms:

Furnished or Provided:
The act of supplying a device or piece of equipment as required meeting the scope of work specified
and making that device or equipment operational. All costs required to furnish the specified device or
equipment and make it operational are borne by the division specified to be responsible for providing
the device or equipment.

Install or Installed:
The physical act of mounting, piping or wiring a device or piece of equipment in accordance with the
manufacturer's instructions and the scope of work as specified. All costs required to complete the
installation are borne by the division specified to include labor and any ancillary materials.

Interface:
The physical device required to provide integration capabilities from an equipment vendor's product to
the control system. The equipment vendor most normally furnishes the interface device. An example of
an interface is the chilled water temperature reset interface card provided by the chiller manufacturer in
order to allow the control system to integrate the chilled water temperature reset function into the control
system.

Integrate:
The physical connections from a control system to all specified equipment through an interface as
required to allow the specified control and monitoring functions of the equipment to be performed via the
control system.
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APPENDIX B: Abbreviations
The following abbreviations may be used in graphics, schematics, point names, and other UI
applications where space is at a premium.
AC - Air Conditioning
ACU - Air Conditioning Unit
AHU - Air Handling Unit
AI - Analog Input
AO - Analog Output
AUTO - Automatic
AUX - Auxiliary
BI - Binary Input
BO - Binary Output
C - Common
CHW - Chilled Water
CHWP - Chilled Water Pump
CHWR - Chilled Water Return
CHWS - Chilled Water Supply
COND - Condenser
CW - Condenser Water
CWP - Condenser Water Pump
CWR - Condenser Water Return
CWS - Condenser Water Supply
DA - Discharge Air
EA - Exhaust Air
EF - Exhaust Fan
EVAP - Evaporators
FCU - Fan Coil Unit
HOA - Hand / Off / Auto
HP - Heat Pump
HRU - Heat Recovery Unit
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HTEX - Heat Exchanger
HW - Hot Water
HWP - Hot Water Pump
HWR - Hot Water Return
HWS - Hot Water Supply
MAX - Maximum
MIN - Minimum
MISC - Miscellaneous
NC - Normally Closed
NO - Normally Open
OA - Outdoor Air
PIU - Powered Induction Unit
RA - Return Air
RF - Return Fan
RH - Relative Humidity
RTU - Roof-top Unit
SA - Supply Air
SF - Supply Fan
SP - Static Pressure
TEMP - Temperature
UH - Unit Heater
UV - Unit Ventilator
VAV - Variable Air Volume
VVT - Variable Volume Terminal Unit
W/ - with
W/O - without
WSHP - Water Source Heat Pump
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