Building Automation System

Building Automation Building Automation SystemSystem

Interfacing to a VAV SystemInterfacing to a VAV System


Interfacing to a VAV SystemInterfacing to a VAV SystemA BAS monitors inputs...A BAS monitors inputs...

AnalogAnalog Return air temperatureReturn air temperature Off-coil temperatureOff-coil temperature Duct static pressureDuct static pressureBinaryBinary Filter clean/dirty statusFilter clean/dirty status Fan hand/off/auto statusFan hand/off/auto status Fan alarmFan alarm Fan statusFan status


Interfacing to a VAV Interfacing to a VAV SystemSystem

... and controls outputs... and controls outputsAnalogAnalog Cooling coil valve position adjustCooling coil valve position adjust VSD setpoint adjustVSD setpoint adjustBinaryBinary Return air dampers controlReturn air dampers control Fan start/stop controlFan start/stop control

AI

BO

BI

AO

AI

VSD

AO

BI

BI

BO

BI

AI

Points in Control PanelFan Speed ControlTrip AlarmAuto/Manual StatusFan Start/Stop Control

CP



Return Air TemperatureReturn Air TemperatureUses a bulb-type sensor.Uses a bulb-type sensor.

Measures temperature of air returning Measures temperature of air returning from space through ceiling plenum.from space through ceiling plenum.

Typically 28°C to 30°C due to heat load Typically 28°C to 30°C due to heat load and heat gain in plenum from lights.and heat gain in plenum from lights.

Indication of average space Indication of average space temperaturetemperature


Return Air Damper ControlReturn Air Damper ControlOnly used when VAV AHU is used for Only used when VAV AHU is used for

pressurization during fire mode.pressurization during fire mode.

Normally, damper is full open to allow Normally, damper is full open to allow return air to mix with fresh air.return air to mix with fresh air.

In fire mode, damper shuts so AHU In fire mode, damper shuts so AHU pressurizes space to assist smoke pressurizes space to assist smoke spill system and control movement spill system and control movement

of smokeof smoke


Filter AlarmFilter AlarmSwitch which closes when Switch which closes when

differential pressure across filter differential pressure across filter exceeds a certain value.exceeds a certain value.

As filter gets dirty, it clogs up and As filter gets dirty, it clogs up and differential pressure increases.differential pressure increases.

When the switch closes the operator When the switch closes the operator is advised to replace the filter.is advised to replace the filter.


Cooling Coil ControlCooling Coil ControlChilled water valve is controlled to Chilled water valve is controlled to

maintain off-coil temperature maintain off-coil temperature setpoint.setpoint.

Actuator can take one of following Actuator can take one of following signals: signals:

Digital communication busDigital communication bus 0-10 VDC0-10 VDC 4-20 mA4-20 mA


Off Coil TemperatureOff Coil TemperatureUses averaging sensor to measures Uses averaging sensor to measures

air temperature after cooling coil.air temperature after cooling coil.

Used to control cooling coil to Used to control cooling coil to achieve an off coil setpoint of 10°C achieve an off coil setpoint of 10°C

to 14°C.to 14°C.

Bulb type supply air temperature Bulb type supply air temperature sensor sometimes used in place of sensor sometimes used in place of

off coil temperature.off coil temperature.


Fan Speed ControlFan Speed ControlSignal from BAS changes setpoint of Signal from BAS changes setpoint of

Variable Speed Drive controller.Variable Speed Drive controller.

Signal from BAS is either 0-10 VDC Signal from BAS is either 0-10 VDC oror

4-20 mA4-20 mA

Variable Speed Drive controller Variable Speed Drive controller sends appropriate signals to fan.sends appropriate signals to fan.


Trip AlarmTrip AlarmVoltage-free contact closes when Voltage-free contact closes when

fan motor trips due to:fan motor trips due to: Motor overloadMotor overload VSD overloadVSD overload

When trip alarm occurs, operator is When trip alarm occurs, operator is alerted and advised to investigate.alerted and advised to investigate.


Auto / Manual SwitchAuto / Manual SwitchIf somebody has taken control away If somebody has taken control away

from the BAS by changing the from the BAS by changing the Hand/Off/Auto switch away from Hand/Off/Auto switch away from

Auto position, the operator is Auto position, the operator is advised.advised.

If switch is Manual position, If switch is Manual position, operator knows that he has no operator knows that he has no

control over the fan.control over the fan.


Fan Start/Stop ControlFan Start/Stop ControlApplies 24VAC signal to control Applies 24VAC signal to control

panel.panel.

VSD manages timing associated VSD manages timing associated withwith

soft-start of fan.soft-start of fan.


Fan StatusFan StatusUses differential pressure switch to Uses differential pressure switch to

give positive feedback of fan give positive feedback of fan operation.operation.


Static PressureStatic PressureControlled by pressure control loop Controlled by pressure control loop

to achieve a setpoint.to achieve a setpoint.


Hardware ElementsHardware Elements



One AHU per controller for One AHU per controller for fault tolerancefault tolerance

Stand-alone DDC control Stand-alone DDC control program stored in Eprogram stored in E22PROMPROM

Each analog input can also Each analog input can also be configured to monitor be configured to monitor two binary inputstwo binary inputs

Default time schedule for Default time schedule for stand-alone operationstand-alone operation

NoNo battery battery

DDCDDCControllerController


Communication Communication network between DDC network between DDC controllers and controllers and Network Control UnitNetwork Control Unit

3 wires, RS-485, 1500 3 wires, RS-485, 1500 feetfeet

Sends start/stop and Sends start/stop and adjust commands from adjust commands from NCU to DDC NCU to DDC controllerscontrollers

Reports all binary Reports all binary change of states to change of states to NCUNCU

Reports analog values Reports analog values when requested by when requested by NCU NCU

N2 BusN2 Bus


Provides BAS features Provides BAS features for associated DDC for associated DDC controllerscontrollers Fault tolerance - no Fault tolerance - no single point of failuresingle point of failure

System performance System performance independent of sizeindependent of size

““PC in a box”PC in a box” 80386 processor80386 processor Up to 10 Meg SIMMUp to 10 Meg SIMM 2 ISA slots2 ISA slots

NetworkNetworkControl UnitControl Unit


Connection points for:Connection points for: Network TerminalNetwork Terminal Notebook PCNotebook PC PrinterPrinter ModemModem

72 hour battery backup 72 hour battery backup of programs and dataof programs and data

Real-time multi-tasking Real-time multi-tasking operating systemoperating system

NetworkNetworkControl UnitControl Unit


Communication Communication between Network between Network Control Units and Control Units and Operator WorkstationsOperator Workstations

Standard 2.5 Mbaud Standard 2.5 Mbaud ARCNET LANARCNET LAN

Coax or fibre, bus or Coax or fibre, bus or starstar

Object oriented Object oriented protocolprotocol

Johnson Controls will Johnson Controls will release protocol release protocol information at no information at no charge charge

N1 LANN1 LAN


IBM Compatible PCIBM Compatible PC Microsoft Windows Microsoft Windows

Graphical User Graphical User InterfaceInterface Scanned Scanned photographsphotographs

Autocad floorplansAutocad floorplans Schematics built Schematics built from symbol from symbol librarieslibraries

Real-time field data Real-time field data superimposed on superimposed on background graphicsbackground graphics

OperatorOperatorWorkstationWorkstation


Historical data from Historical data from NCU is archived in NCU is archived in dBase filesdBase files NCU can archive NCU can archive data in multiple data in multiple workstations workstations concurrently so that concurrently so that data is not lost if PC data is not lost if PC failsfails

Other Windows Other Windows programs can run programs can run concurrentlyconcurrently

Other software can Other software can access BAS data using access BAS data using Dynamic Data Dynamic Data Exchange (DDE)Exchange (DDE)

OperatorOperatorWorkstationWorkstation


Hand held device for Hand held device for system access outside system access outside of control roomof control room

Can be connected to Can be connected to NCU or at remote NCU or at remote connectionconnection

User friendly “finger User friendly “finger mouse” operationmouse” operation

Access to all system Access to all system data including data including historical datahistorical data

Point names and Point names and password consistent password consistent with PCwith PC

NetworkNetworkTerminalTerminal


Fire Panel IntegrationFire Panel Integration

Chiller PanelChiller PanelIntegrationIntegration


Third Party IntegrationThird Party IntegrationA number of vendors have released A number of vendors have released

their communication protocol to their communication protocol to Johnson Controls.Johnson Controls.

Joint testing is done to ensure that the Joint testing is done to ensure that the high level interface does not high level interface does not

interfere with the proper operation interfere with the proper operation of the third party system.of the third party system.


Software FeaturesSoftware Features


Limit unauthorized Limit unauthorized accessaccess

5 levels of access5 levels of access MonitorMonitor Monitor, ControlMonitor, Control Monitor, Control, ModifyMonitor, Control, Modify Monitor, Control, Modify, Monitor, Control, Modify,

ProgramProgram Monitor, Control, Modify, Monitor, Control, Modify,

Program, PasswordProgram, Password Same password used at Same password used at

PC and Network PC and Network TerminalTerminal

Encrypted database Encrypted database stored at each PC and stored at each PC and each NCUeach NCU

PasswordPassword


Network Map

Network MapNetwork Map

JCTower

Vent

Electric

Air_Con

Level_05

AHU_05 Level 5 Air Handling Unit

VAV_05 Level 5 VAV Terminal Units

Level_04

Level_03

+

-

+

-

-

+

+

Graphic Window


Graphic Window

Graphic Window

Graphic PenetrationGraphic Penetration


All information about a All information about a point in one summarypoint in one summary

Line graph showing Line graph showing samples over past 24 samples over past 24 hours for analog pointshours for analog points

Dynamic line graph Dynamic line graph which updates every 20 which updates every 20 seconds for analog seconds for analog pointspoints

Last 10 change-of-states Last 10 change-of-states (ON/OFF) with time/date (ON/OFF) with time/date for binary pointsfor binary points

Point FocusPoint Focus


Point Focus Window

BuildingSystem

Point

History Current

30.0

10.0

10/10/94 07:00 16.730.0

10.0

10/10/94 12:07:15

12.3

Point Focus WindowPoint Focus Window


Point Focus Window

BuildingSystem

Point

History Current

30.0

10.0

10/10/94 07:00 16.730.0

10.0

10/10/94 12:07:15

12.3

Alarm MessageAlarm Message

CRITICAL ALARM EVENT

10/10/94 12:07:17 Building\System\Point 15.0 Deg C Hi AlarmTemperature is outside of normal operating range - ensure valve is under control

Look Now Look Later Discard View System


Alarm MessageAlarm Message

Alarm eventdetected at

NCU

Alarm message routedto multiple PCs

Alarm message routedto remote locationthrough modem


Distribution system for Distribution system for messages and filesmessages and files

Manages alarm Manages alarm messages, Totalization messages, Totalization files, Trend files and files, Trend files and Point History filesPoint History files

Concurrent updating of Concurrent updating of multiple locations for multiple locations for fault tolerancefault tolerance

Feature executed by Feature executed by each Network Control each Network Control Unit for fault toleranceUnit for fault tolerance

Report Router /Report Router /Alarm ManagerAlarm Manager


Archiving of Historical FilesArchiving of Historical Files

Historicalfile stored

in NCU

Copy of file archivedin multiple PCsin dBase format

Copy of file sentto remote locationthrough modem


Maintains records of run-Maintains records of run-timetime

Allows scheduling of Allows scheduling of preventive maintenance preventive maintenance based on usagebased on usage

Data archived in multiple Data archived in multiple PCs for fault tolerancePCs for fault tolerance

Built-in graphing Built-in graphing functionsfunctions

Data can be exported to Data can be exported to other applications such other applications such as Maintenance as Maintenance Management softwareManagement software

TotalizationTotalization


Periodic sampling of Periodic sampling of selected pointsselected points

12000 samples kept in 12000 samples kept in each NCUeach NCU

Samples archived in Samples archived in multiple operator multiple operator workstations for fault workstations for fault tolerancetolerance

Built-in graphing Built-in graphing functionsfunctions

Data available to third Data available to third party softwareparty software

TrendTrend


Continuous record of all Continuous record of all points in the BAS Systempoints in the BAS System

Allows proactive Allows proactive response to occupant response to occupant complaints or alarmscomplaints or alarms

Data available at all Data available at all Operator Workstations Operator Workstations and Network Terminalsand Network Terminals

Unique feature only Unique feature only available with Metasysavailable with Metasys

Point HistoryPoint History

Building Automation Building Automation SystemSystemTrend OnlyTrend Only Point HistoryPoint History

I will start collecting datanow and hope that the same

problem happens again.

I always have thedata required before

I need it.


Automatic execution of Automatic execution of commands or summaries commands or summaries based on a time based on a time scheduleschedule

One time schedules to One time schedules to accommodate special accommodate special situationssituations

Automatic updating of Automatic updating of point status after a point status after a power failurepower failure

Report generation by Report generation by each NCU for fault each NCU for fault tolerancetolerance

Default schedules in Default schedules in each DDC for fault each DDC for fault tolerancetolerance

SchedulingScheduling


Advanced energy Advanced energy management algorithmsmanagement algorithms

Actions co-ordinated Actions co-ordinated between featuresbetween features

Prioritization of loadsPrioritization of loads Built-in safety Built-in safety

parametersparameters Utility Profile to track Utility Profile to track

electricity billselectricity bills

Demand LimitingDemand Limiting/ Load Rolling/ Load Rolling


Remote PC can access Remote PC can access networknetwork

Remote telephone can Remote telephone can access network in tenant access network in tenant mode or operator modemode or operator mode

Critical alarms directed Critical alarms directed to:to: Remote printerRemote printer Remote telephone Remote telephone

(voice synthesis)(voice synthesis) Numeric pagerNumeric pager Text pager Text pager

Dial-Up I/ODial-Up I/O

Building Automation System

Documents