EMCS Section 15910 - Alberta Ministry of Infrastructure
Contents
1. Install termination resistor Run communications wiring in 13mm EMT and input output wiring in 19mm EMT 32 6 6 6 7 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls TRAINING OF OPERATORS l Provide 1 2 day factory training courses covering the following l OB wi Tour of mechanical system and overview of system schematics O amp M Manual and Teacher s Guide Detailed explanation of operating modes and sequences of operation Method for changing setpoints schedules and occupancy override Basic trouble shooting Very basic description of programming configuration tool Provide a list of all vendor s in Alberta that can provide post warrantee service on the supplied controls 2 Class size should not be more than 20 Provide a sign off sheet for inclusion in the system documentation manuals 3 Training must be performed at Alberta location on a fully functional classroom identical to owner s units Provide option for on site training Note No cost on site training should be offered to boards that have purchased a number of high performance modular classrooms Perhaps one session per 10 units purchased A Although not related to controls training should include a few words on proper site preparation and classroom installation MISCELLANEOUS l Programming Configuration tool Manuals O amp M Manual Disk Backup Package and two copies of the Teacher s Guide to be stored in a2. Parameter RC OCCschd Internal schedule option units Yes No default value Yes Occupancy is determined via the internal weekly schedule RC OCC_WS and annual schedule RC OCC_AS If set to No then occupancy is assumed to be determined via the occupancy sensors Initially set up weekly scheduled occupied hours between 7 30AM and 6 00PM Monday through Friday Set up annual holiday schedule for the major holidays and summer vacation from mid July through to mid August School operator custodian will need to make final adjustments on receipt of classroom 10 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 10 NOTE If connected to school s EMCS set the schedule option to yes and download schedules from EMCS As an alternative set this option to yes and create a program in the EMCS to override the status of the internal weekly and annual schedule based upon the status of he EMCS s schedules Parameter RC OCCtclk Hardwired time clock option units Yes No default value No Set parameter to Yes to indicate that occupancy is to be determined via the external time clock input RC TC This takes precedence over the internal weekly and annual schedules Ideally setting RC OCCtclk to Yes would automatically reset RC OCCschd to No As an alternative it should not be possible to set RC OCCtclk to Yes if RC OCCschd is already Yes Parameter RC OC
3. vendor to specific methods of programming or diminish their responsibility for producing a reliable product More efficient strategies and techniques are welcome as long as the functionality described in this guideline is incorporated and comfort and energy efficiency are not compromised 3 2 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 10 Controls programming MUST take into account the possibility of improper user input Humans are fallible and make entry and judgment errors Setpoints and other input should be checked for reasonableness etc There should be no way the unit could be placed into an operating mode that would lead to premature equipment failure no matter how long the unit operates under these conditions Error messages should help guide the user to the correct action without implying a negative context For example it would be better to say Occupied setpoint must be within comfort range 21 to 24 degC rather than simply Illegal entry without any indication of what was entered or what is the allowed range BUILDING OPERATING MODES Three fundamental modes of operation are defined zl Occupied Normal operation space at normal occupied setpoint main fan continuous operation exhaust fan and mixing dampers set to provide required outside air with free cooling capability and heating cooling are enabled Pressing the thermostat s occupancy button will put the space into occupied
4. 300 V insulation allowed for conductors not entering enclosures containing line voltage 120 VAC Control Wiring minimum 14 AWG Low Voltage Field Wiring Minimum 22 AWG Twisted pairs Stranded except 18 AWG and larger may be solid Shielded with drain wire except for digital input output wiring carrying less than 25mA and not installed in tray 5 Multi conductor wiring must have individually twisted and shielded pairs with a drain wire for each pair Cable must have overall shield Maximum 6 pairs PUN Plenum rated cable to be FT4 rated 30 6 3 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 5 Neatly arranged panduit with snap on covers shall be used to restrain wiring inside cabinets larger than 300mm square Neatly train and cable tie wiring in cabinets smaller than 300 mm square Adhesive backed twist ties or adhesive backed cable tie holders are not allowed Wiring shall be secured to cabinet back with mountable cable ties fastened with 8 or larger sheet metal screws Each field device shall have its own signal and return wire individually terminated in the panel The use of a common return wire or ground for more than one control point is not allowed Plenum rated cable shall be secured to the building structure at intervals not exceeding 2 meters Attaching cable to the ceiling support system is not allowed A single continuous non spliced cable shall be used for connecti
5. No RWTO RC HR_DFRSTdur Defrost cycle duration minutes RWTO RC HR_DFRSTper Defrost cycle period hours RWTO RC L_INTMR Lighting Interupt Timer On Off RWTO RC CO2_SP CO2 Setpoint PPM RWTO RC CO2_HIALM CO2 High Alarm Alarm Normal RTA RC CO2_FAULT CO2 sensor fault Alarm Normal RWTOA RC ADTIME Decimal 24hr Time Hrs RT Control Sequences GENERAL wl In many ways the older standalone portables were somewhat less problematic because these mechanical systems were very simple in nature and the typical thermostat interface was generally straight forward in nature and well understood by most people Unfortunately the older mechanical systems did not provide good comfort conditions were not energy efficient and could not be counted on to provide the required amount of outside air for proper ventilation Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 2 In response to indoor air quality concerns and energy efficiency the current high performance modular classrooms have mechanical and control systems that are much more complex Heating is now modulated or at least staged mixing dampers modulate in response to space demands mechanical cooling may be available and heat reclaim is now standard Occupancy can be scheduled or sensed and lighting controls can be simple overrides or include daylight harvesting Resulting control sequences are not only lengthy but more highly integrated 3 Programmi
6. any of the above settings 7 The mechanical system may use a modulating or multistage gas valve or even some other form of heating The system will also use some form of heat recovery This may be in the form of a heat wheel heat pipe or air to air heat exchanger with built in exhaust fan The programming must be written such that these differences are hidden from the basic operational profile As an example heating is to be a value between 0 100 This can directly represent a modulating gas valve or electric heating coil Multistage firing rates would show as stepped values i e 4 stages would be 25 50 75 100 Special vender specific setup parameters could be made available via additional product specific objects options 8 Although mechanical cooling may not be installed when a high performance modular classroom is constructed many boards add cooling soon after delivery Direct DX cooling control point RC CLG and or cooling system enable point RC CLG_E must be provided as well as all related control strategies Parameter RC CLG_INSTALLED units Yes No is used to enable disable control of cooling 9 It is not necessary to create programming exactly as shown in the following articles The sample programming uses various techniques and mixed mode mathematics that are not available to all systems Such details should be treated as a guideline as to how the sequences are to operate It is not the intent of this guideline to limit the
7. lockable cabinet in the mechanical space Label cabinet with MANUALS Two copies of the Teacher s Guide to be stored in a pouch mounted on the front surface of the cabinet END OF GUIDELINE 33 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls Relocatable Classrooms SAMPLE Point Sheet Systems RC 1 Pkg Alarm Flame Fail etc Page 1 of 1 Januaryr 2009 2 Supply Fan Continuous Operation Include HOA 3 Exhaust Fan Include HOA 4 Humidifier Solonoid etc 5 Gas Valve Low Fire 2 stage 1st stage of heating NOTE A Include HOA 6 Gas Valve High Fire 2 stage 2nd stage of heating NOTE A Include HOA 7 Gas Valve Modulating Modulating gas valve NOTE A Include HOA 8 DX Cooling CLG Do not allow activation below 15 degC OAT 9 Mixed Air Temperature MAT Locate in well mixed portion of air stream 10 Supply Air Temperature SAT Locate in supply duct 11 Mixed Air Dampers MAD gt gt WS W S S S W W S gt Belimo or equivalent actuators Include HOA 12 Relief Air Damper RAD Belimo or equivalent actuators Include HOA Net Sensor User Interface 13 Timed Occupancy Manual Override Switch OCCMOR 14 Space Temperature ST Locate on classroom side of mech room wall 15 Space Relative Humidity RH Locate on classroom side of mech room wall 16 CO2 Concentration
8. mode 3 Do not defrost when outside air temperature is above freezing or system is in unoccupied mode 3 Generally heat reclaim would be used during occupied mode when outside air is being introduced into the classroom However it is to be disabled whenever this function would decrease overall energy efficiency or comfort For example if its warm outside but room temperature is warmer still then running the reclaim will just warm the incoming air and reduce its ability to cool the space LIGHTING CONTROL 20 3 8 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls For safety and security reasons lighting must be able to be turned on as soon as there is any indication of occupancy Therefore enable power to lighting contactor RC L as soon as occupancy sensor has had a capture i e whenever RC OCC_PROB gt 30 In general lights are to be operational whenever the space is in occupied mode However when the energy savings option is active the lights are to be turned off when the there is no sensed occupancy even if the class is in occupied mode To ensure there are no surprises the lights are pulsed off for 1 second about 5 minutes before they would be turned off i e as RC OCC_PROB drops below 20 This allows time for any occupants to reinstate normal occupied mode control with a simple wave of the hand etc The logic can be summarized as follows If RC OCC_TMR gt 0 i e occupancy ma
9. mode operation for the number of minutes contained in variable RC OCC_MORT The transition into occupied mode is also to incorporate warm up and purge functions as follows a Warm up This function is active whenever the space temperature is noticeably below setpoint as would occur during startup after a night setback period or with an equipment failure During this mode the amount of fresh air is smoothly decreased to allow for greater heating capacity and quicker recovery as follows Temp below setpt Max allowed mixing damper position 3 degC 0 fully closed 0 5 degC 100 or as desired by normal programming Mixing damper position Exhaust Fan Less than 1 2 of RC AMAD_MIN OFF Greater or equal to RC MAD_MIN ON 2 Purge This function simply disables mechanical DX cooling during the first 20 minutes of occupancy 3 3 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 2 Occupied with Energy Savings Active This is similar to the regular occupied mode but includes features to conserve energy if no actual occupancy is being sensed As the probability of occupancy drops below 20 the lights are pulsed off for one second mixing dampers slowly close over 5 minutes and the exhaust fan goes off once the dampers have closed to less than 2 of their minimum ventilation position The one second lighting interruption notifies any occupants that there has been insufficient activity to indicate occupancy an
10. of major mechanical failure Items are to include l Thermostat or user interface failure Power problem Control panel still working Etc 2 Control panel failure Power problem How to manually position the mixing dampers How to manually override the fan Ete 3 Classroom extreme low temperature Control panel or furnace problem How to manually close the outside air dampers How to manually engage heating i e gas valve etc and fan Etc Controller Hardware and Software PROGRAMMABLE CONTROL UNIT PCU amp INTELLIGENT THERMOSTAT The PCU is to be a single stand alone custom programmable NOT simply configurable native BACnet controller Included interfaces to allow connection to a larger BACnet system via a network to share information execute commands or save load database and control sequences from a Central Control Station and or laptop computer Provide ALL of the following l IEEE 802 3 Ethernet 10 100 Base T BACnet over IP 2 EIA 485 up to 76 8 kbps BACnet MS TP 3 Serial EIA 232 BACnet PTP 38400kbbs minimum Memory capacity and point configuration to suit application plus one spare universal input and one spare analogue output 27 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 5 2 Watchdog timer Failure of PCU shall automatically switch outputs to a pre selected fail safe condition Real Time Clock function with programmable scheduling Permane
11. self contained with occupancy determined by internal weekly and annual schedules Mechanical systems and lights operate during occupied hours regardless of occupancy sensor readings During unoccupied hours the occupancy sensor only enables lighting the mechanical system remains in night setback mode 3 Controls completely self contained similar to 2 above but occupancy sensor is also used in occupied mode to save extra energy by decreasing outside air intake and turning out the lights when no occupancy is sensed This is the default mode of operation A Controls interfaced to simple time clock Similar to 2 above but external contact input is used instead of internal schedules Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 5 Controls interfaced to simple time clock similar to 4 above but occupancy sensor is used in occupied mode to save extra energy by decreasing outside air intake and turning out the lights when no occupancy is sensed 6 Controls interfaced to school EMCS Similar to 4 or 5 above but school s EMCS can be programmed to override classroom s internal occupancy schedules energy savings option flag as well as the various setpoints If necessary it would also be possible to perform these as well as other functions manually from offsite 7 Manual activation of override timer forces mechanical system into normal occupied operating mode for a predetermined interval irrespective of
12. to improve environmental conditions for the students 4 Since the mechanical system requires some form of heat reclaim the amount of energy to be saved by CO2 control is diminished Decreasing the flow rate of fresh air must be balanced by decreases in exhaust rates On off control of the exhaust fan is not an adequate means of control in an occupied classroom some form of speed control or modulation is required This complicates an already complicated mechanical system 5 Decreased air flow through the heat reclaim will make certain types significantly more efficient which is beneficial in one respect but it also makes the unit much more prone to frost and ice buildup Increased defrosting may be required Water pooling in the unit in never a good thing ALARM PROGRAMS Enable mechanical alarm output RC MALM when any of the following critical alarms is detected Low space temperature via RC ST lt 12 degC Mechanical system failure via RC FAULT High sump alarm via RC SUMP_HI Intelligent thermostat user interface failure LuNe It is understood that a simple furnace does not have an available fault output contact for RC FAULT but it is assumed that other information will be used in conjunction with low classroom space temperature to provide similar functionality For example If classroom temperature is below setpoint and the furnace is supposed to be firing in low or high fire and the supply air temperature has been below 3
13. 0 RC HTG RC HMAD RC ICLG NOTE If cooling is not available i e RC CLG_INSTALLED is No then limit control loop output to values between 0 and 75 NOTE Controller response must be tuned so as to ensure slow smooth operation The output must not cause the cooling DX or heating gas valves to cycle more than about 6 times per hour Separate control over mixed air temperature is often desired This can be incorporated into the above scheme by resetting mixed air temperature setpoint RC MAT_SP with respect to supply air temperature controller position as follows RC ST_CO RC MAT_SP 75 or greater 13 degC 45 or less 23 degC 16 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 10 ll 12 13 14 Allow cooling only while RC SF is ON AND occupied mode RC OCCUPIED is Yes AND outside air temperature RC OAT is greater than 18 degC Disable DX cooling when RC SF goes OFF OR RC OCCUP is No OR RC OAT drops below 15 degC Also disallow cooling during the warm up purge phase that is the first 20 minutes of occupancy When enabled for operation control cooling as follows RC ST_CO RC CLG 95 or greater ON 75 or less OFF NOTE Do not allow more than 6 cycles per hour Mixing dampers RC MAD modulate over controller RC ST_CO output range of 45 dampers full return air up to 75 dampers full to outside air OR if separate mixed air temperature control
14. 0 degC for the last 15 minutes then it can safely be assumed there is a furnace failure and a virtual RC FAULT value can be set to TRUE Display an alarm on the intelligent thermostat when any of the following non critical alarms is detected 23 4 1 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls wl RC CO2_HIALM high CO2 level via RC CO2 gt 1000 PPM for 30 min if CO2 device is available 2 RC CO2_FAULT CO2 sensor fault if CO2 device is available Documentation CONTROLS O amp M MANUAL O amp M DISK AND SYSTEM BACKUP ol Provide one complete copy of a Controls Operation and Maintenance Manual as follows l Divisions 1 Controls Hardware Configuration Installation 2 Controls Software Database Programming 3 Controls Maintenance 4 O amp M Disk full manual in electronic format 5 Backup Disk A D ring binder with two plastic sheet lifters and clear outside overlay pockets is acceptable Binder cover and spine shall display the project title classroom model date of manufacture serial number and manufacturer s name The cover sheet should also have DO NOT REMOVE FROM CLASS MECHANICAL ROOM in bold red near the bottom Other information and logos may be added to the cover as desired 2 Controls Hardware Configuration Installation l Organize the information into sections with index and divider tabs as follows l Configuration include explanations of a
15. ALBERTA INFRASTRUCTURE GUIDELINE FOR HIGH PERFORMANCE MODULAR CLASSROOM CONTROLS 2013 Capital Projects Technical Services Branch 1 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls Table of Contents 1 1 INTENT 2 1 2 ABBREVIATIONS 2 1 3 BASIC MECHANICAL amp ELECTRICAL REQUIREMENTS 2 STANDARD FUNCTIONAL PROFILE cccsscsssssssssssssssssscssssssssssscscssssssssessessesseees J 2 1 GENERAL 3 2 2 BASIC OPERATIONAL OBJECTS 4 23 ENGINEERING MAINTENANCE RELATED OBJECTS 4 3 1 GENERAL 6 3 2 BUILDING OPERATING MODES 9 3 3 DEFINITIONS SETUP PARAMETRS AND SYSTEM VARIABLES 10 3 4 BASIC DATA GATHERING 13 3 5 DETERMINATION OF OCCUPANCY 14 3 6 PACKAGED HVAC UNIT CONTROL DETAILS 16 3 7 LIGHTING CONTROL 20 3 8 EMERGENCY CONTROL 21 3 9 CO2 MONITORING AND CONTROL 22 3 10 ALARM PROGRAMS 23 4 1 CONTROLS O amp M MANUAL O amp M DISK AND SYSTEM BACKUP 24 4 2 TEACHER S GUIDE 26 4 3 EMERGENCY PROCEDURES SHEET 27 CONTROLLER HARDWARE AND SOFTWARE ccssssssssssssssssssssscssssssssesssees 27 5 1 PROGRAMMABLE CONTROL UNIT PCU amp INTELLIGENT THERMOSTAT 27 5 2 PROGRAMMING CONFIGURATION TOOL AND MANUALS 28 6 1 OCCUPANCY AND LIGHT SENSORS DEVICES 30 6 2 WIRING AND INSTALLATION 30 6 3 IDENTIFICATION 31 6 4 GROUNDING 32 6 5 SCHOOL INTERFACE CABINET AND TERMINAL STRIP 32 6 6 TRAINING OF OPERATORS 33 6 7 MISCELLANEOUS 33 1 1 1 2 1 3 Alberta Infrastructure Guideline for High Performa
16. CO2 wiw gt Carbon dioxide concentration PPM Miscellaneous 17 Occupancy Sensor OCCS Mount to view blackboard and front desks 18 Room Lights L N C contact Interupt power to switches 19 Sump High Level Alarm SUMP HI 20 Mechanical Alarm MALM Wire to school interface terminal strip 21 Time Clock TC Wire to school interface terminal strip 22 Outside Air Temperature OAT Mount in fresh air intake 23 Spare Al Input Spare WO CO W WS Spare universal input point 24 Spare AO Output Spare2 Spare universal output point Include HOA NOTE A All heating unit safety interlocks to remain Gas valve type to be determined during system design NOTE All points under same group letter must be in same control panel
17. Cesave Energy savings option units Yes No default value Yes When enabled the occupancy sensor is used to save extra energy when no occupancy is sensed during occupied conditions by turning out the lights as well as decreasing outside air intake during cold or extremely hot weather NOTE This option makes no difference in manual occupancy override mode It is assumed someone wants everything up an running no matter what the actual occupancy Parameter RC OCCco2 CO2 control option units Yes No default value No If available the CO2 sensor is used to save extra energy by decreasing outside air quantities requirements during occupied conditions during cold or extremely hot weather Variable RC OCC_MORT Occupancy Manual Override Time units Minutes default value 60 entry limited to values between 30 and 240 This is the duration that the system will be put into occupied mode whenever the intelligent thermostat s occupancy manual override button RC OCCMOR is momentarily depressed Variable RC OCC_TMR Manual Occupancy Count Down Timer units Minutes default value 0 This timer indicates the number of minutes remaining in occupied mode since the momentary closing of the intelligent thermostat s occupancy manual override button The timer automatically counts down to zero and is set to the manual override time value RC OCC_MORT whenever button RC OCCMOR is depressed 11 Alberta Infrastructur
18. GROUNDING Provide a complete ground system for all PCU equipment including panels conductors conduit raceways connectors and accessories Grounding shall be by means of electrical supply conductor bonding method Separate grounding conductors not permitted Grounding between control panels and field devices shall have a star configuration The shield for a field device shall be grounded at the panel only The shield for communications wiring must be contiguous throughout its full length and shall be grounded at one point only For intelligent thermostats the ground shall be at the PCU Splices shall expose no more than 2cm of unshielded wire SCHOOL INTERFACE CABINET AND TERMINAL STRIP Supply and install a 250m square 100mm deep junction box on the wall 50mm above ceiling tile height on the hallway side of the classroom Install one 10 position terminal strip and one RJ 45 Ethernet receptacle within the box and affix with 8 screws Connect this junction box to the PCU cabinet with a 19mm EMT and a 13mm EMT School interface strip Provide separation between the output and input locations Wire points to PCU and ensure shield and drain wires are taken back to PCU and terminated there Affix a layout sheet on the door inside surface Label locations as follows Wire pair 1 Mechanical Alarm relay output Wire pair 2 Spare Wire pair 3 Time Clock dry contact input Wire pair 4 shield EIA 485 School Network BACnet MS TP
19. Option Yes No RWO RC OCCesave Occupancy EnergySave Option Yes No RWO RC OCCco2 CO2 Control Option Yes No RWO RC CLG_INSTALLED Cooling Available option Yes No RWO RC OCC_MORT Occupancy Manual Override Time min RWO RC OCC_TMR Manual occupancy count down timer min R RC OCC_WS Occupied Mode Weekly Schedule RWTO All schedule setup parameters RW 3 1 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls RC OCC_AS Occupied Mode Annual Schedule RWTO All schedule setup parameters RW RC OCC_PROB Occupancy Probability RWTO RC AST_SP Operating Space Temp Setpoint degC RWTOA RC ST_SPmax Max allowed SpaceTemp setpt degC RW RC ST_SPmin Min allowed SpaceTemp setpt degC RW RC ST_NSP Night setback space temp setpoint degC RWTO RC ST_CO Space Temp Controller Output Value RWTO All control loop setup parameters RW RC AST_PG ST Loop Proportional Gain RWO RC ST_IG ST Loop Integral Gain RWO RC RH_SP RH Setpoint RWTO RC ASAT_SP SAT Setpoint degC RWTO RC MAT_SP MAT Setpoint degC RWTO RC MAT_CO Mix Air Temp Controller Output Value RWTO All control loop setup parameters RW RC AMAT_PG MAT Loop Proportional Gain RWO RC AMAT_IG MAT Loop Integral Gain RWO RC MAD_MIN Mixed Air Damper Min Posn RWTO RC HTG Heating element output value RT Note multi stage firing value would also be shown in of fire i e 50 100 RC HR_DFRST Heat Reclaim in Defrost mode Yes
20. cessively Typically do not allow more than about 6 on off cycles per hour An electric coil may be controlled with a solid state relay that is pulse width modulated under software control 19 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 18 19 20 Space relative humidity setpoint RC RH_SP is calculated as a reset function with respect to outside air temperature as follows RC RH_SP RCH OAT 15 35 degC or lower 30 0 degC or higher Enable humidification device RC H if the space relative humidity RC RH is at least 5 RH below setpoint RC RH_SP AND supply fan RC SF is On AND occupied mode RC OCCUPIED is Yes Turn off humidification if there is a sump alarm via RC SUMP_HI is Alarm OR RC RH is above setpoint OR supply fan RC SF is Off OR occupied mode RC OCCUPIED is No For systems with heat reclaim wl Provide software and additional sensors and controls as necessary to ensure reliable operation of the heat reclaim device under all outside conditions with minimum downtime for defrosting etc 2 As a minimum provide defrost control based upon outside air temperature as follows l Reset RC HR_DFRSTper with respect to outside air temperature OAT DegC RC HR_DFRSTPer hours 30 of less 4 hours 10 or more 12 hours 2 Set RC HR_DFRST to Yes for a duration of RC HR_DFRSTdur minutes every RC HR_DFRSTper hours from start of occupied
21. d all that is required is a single activation of the occupancy sensor to reinstate normal occupied mode control eS Unoccupied Space at night setback temperature supply fan off except as required to intermittently heat the space exhaust fan off and dampers fully closed to outside air This mode is entered directly if an external time clock or network override indicates that occupancy has ended However if occupancy is being determined using the sensors then the stepped response used with the energy savings option precedes final system shutdown DEFINITIONS SETUP PARAMETRS AND SYSTEM VARIABLES In the following control sequence descriptions PHYSICAL POINTS are shown in bold and capitalized and VIRTUAL POINTS are shown in bold and capitalized italics All parameters listed below must be able to be setup via an attached portable computer or network connection to a central control station or directly at the keypad of the smart thermostat keypad NOTE Keypad access to these settings must be protected with a pass code or similar means Parameter RC CLG_INSTALLED Cooling installed units Yes No default value No Set this parameter to Yes if DX Cooling has been installed and is available Parameter RC MAD_MIN Minimum mixed air damper position units default value as required to ensure about 212 L s of outside air will be provided while the exhaust fan is running i e typically somewhere between 30 and 40
22. e Guideline for High Performance Modular Classroom Controls ll 2 13 14 15 Variable RC OCC_PROB Occupancy Probability units of default value 0 This is a value that indicates the likelihood that the classroom is occupied In the following sequence the occupancy sensor must produce 3 captures within a short time to provide 99 probability and since the value is always being decreased one activation every 6 6 minutes is required to keep probability above zero This so called probability of occupancy goes from 100 to zero if nothing has been sensed in 20 minutes As an added feature the probability value is limited to 33 when schedules are enabled but indicating unoccupied OR a hardwired time clock is being used but is also indicating an unoccupied period This allows for a much faster timeout should someone just pop in for a few moments to pick something up or whatever During manual occupancy override probability is not valid because all systems are forced ON Just set value to 33 while in manual mode so probability is already limited when counter times out Should there still be significant occupancy in the space the probability will climb and the systems will remain in occupied mode as desired Every 3 seconds do all of the following If RC OCCS is ON Then increase the value of RC OCC_PROB by 33 Else decrease the value of RC OCC_PROB by 0 25 Limit RC OCC_PROB to values between 0 and 100 If RC OCCtclk i
23. eens Descriptions and Procedures Provide a description of overall control philosophy Describe all hardware interlocks with other equipment that may affect or override action of software control modules Provide procedures for operating staff to interface with software control modules to override system or component operation to adjust system control setpoints etc Name virtual points provided in software for this purpose and recommend adjustment increments and limits where applicable PCU Provide the following information separated with coloured sheets l List of physical and virtual point mnemonics with a detailed description of the meaning of each mnemonic 2 For each User Control Language Program module in the PCU provide l a description of purpose and logic of module 2 a hardcopy listing of the program module 3 Complete hardcopy listing of the database Include each hardware point virtual point schedule report trend controller etc 4 Controls Maintenance l Provide a description of maintenance procedures for all equipment and systems Include a schedule for recommended planned and preventative maintenance work and intervals Include a list of resources to call upon for maintenance and servicing of equipment Provide the supplier s name address and phone number as well as the service contact 25 4 2 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 5 O amp M Disk full manual i
24. equired for each stage RC HTG becomes a virtual point related to the stages as follows RC ST_CO RC HTG 0 20 20 40 Heating Stage 50 100 High fire ON 90 OFF 60 0 50 Low fire ON 40 OFF 10 18 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 16 17 5 Some heating devices cannot be controlled directly by the PCU These generally have self contained controls that maintain the supply air temperature at some setpoint value RC SAT_SP The PCU can be interfaced to these types of controllers with enable RC HTG_E and reset RC HTG_R RC HTG again becomes a virtual point and is used to reset the supply air temperature setpoint The values shown in the tables are included as an examples only Actual numbers should reflect the needs of the supplied mechanical equipment For a heating device with a high turn down ratio RC AST_CO RC HTG RC HTG_R 0 100 full heat As required for SAT setpoint of 55 degC 45 0 no heat As required for SAT setpoint of 22 degC RC AST_CO RC HTG_E 50 or more heating disabled 35 or less heating enabled For a heating device with a 4 1 turn down ratio RC ST_CO RC HTG RC HTG_R 0 100 full heat As required for SAT setpoint of 55 degC 35 0 minimum heat As required for SAT setpoint of 30 degC RC ST_CO RC HTG_E 45 or more heating disabled 30 or less heating enabled Ensure heating equipment does not cycle ex
25. er the possibility of a couple of students working quietly and also provide a somewhat faster response for a larger active group The programming must even handle the situation where a group has been working very quietly sensed occupancy is about to expire and the lights have just been pulsed off to indicate they will be going fully off in the next 5 minutes Any activity within the remaining time should markedly delay the onset of unoccupied mode It also seems reasonable to limit automatic activation to hours between 6 00AM and 10 00PM The manual override button can be used outside these hours Since there are multiple occupancy inputs response must be based upon their priority Occupancy manual override has highest priority and the time clock has precedence over the schedules sensed occupancy has the lowest priority RC OCC_PROB already provides much of the required functionality for sensing occupancy It ramps up far too quickly but can still be used with a suitable delay mechanism The complete sequence can be summarized as follows If RC OCC_TMR gt 0 i e occupancy manual override is active OR RC 0CCtclk is Yes AND input RC TC shows occupied OR RC 0CCiclk is No AND RC OCCschd is Yes AND schedules are showing an occupied state OR RC 0CCitclk is No AND RC OCCschd is No 14 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls AND RC OCC_PROB has been c
26. g of all controller data bases and custom controls sequences via a portable computer connected to the PCU Include any required interface device cable hardware NOTE If many high performance modular classrooms are being provided to one school division board then only provide development tools to a maximum of 3 complete packages If the board already has the required software tools then only upgrade these packages to current version Development tool to include a control sequence editor that wl has full screen editing of program source code 28 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 2 uses graphic display drag and drop graphic representations and graphic linking of objects for block language type languages 3 automatically changes all program occurrences of a point mnemonic if that point mnemonic is changed in data base A flags undefined point mnemonics if a point is removed from the data base 3 Development tool to provide facility to change the Ethernet address of any BACnet over IP Ethernet enabled classroom controller as well as have the ability to change the controller s BACnet device instance This is required when networking multiple BACnet controllers since only one unique BACnet device instance is allowed on a BACnet network A Include a development tool user s manual as well as a programming instruction manual listing all procedures functions operators and reserved word
27. hnical language Pictures and graphics should be used as much as possible to illustrate operations and concepts Include information as follows l Display Screen Show screen layout and displayed information such as room and outside air temperature relative humidity occupancy and operating mode if applicable Graphics and or annotated pictures of actual displays should be included 2 Keypad Show keypad layout label each key and provide basic information as to operation of each key 3 Operation Pictorially and textually guide the casual user through the use of the basic thermostat menu options such as setting temperature setpoint occupancy override and setting light level if available A Occupancy Sensing Provide a clear description of how the occupancy sensor works how it is used to determine occupancy and what are the differences between occupied and unoccupied modes of operation 5 Reporting Describe any reporting features such as alarms if these are displayed on the screen 26 4 3 5 1 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 6 Green Initiative Provide a section on the importance of occupant comfort and indoor air quality Describe the energy conservation features of the classroom mechanical equipment EMERGENCY PROCEDURES SHEET This laminated sheet is to provide school maintenance staff with basic trouble shooting and manual override procedures to be followed under conditions
28. is being used then modulate mixing dampers RC MAD over controller RC MAT_CO output range of 0 dampers full return air up to 100 dampers full to outside air Smoothly limit damper position during warm up based upon the difference between classroom space temperature and setpoint as follows Space Temp below Setpoint Max allowed mixing damper position 3 degC 0 fully closed 0 5 degC 100 fully open To ensure smooth start up or restart during colder weather slow the speed of damper opening such that they cannot go from fully closed to fully open in less than 10 minutes However allow them to close quickly if required Include an economizer function such that mixing dampers RC MAD close to minimum position RC MAD_MIN when the outside air temperature RC OAT is 2 degC above space temperature RC ST The dampers are to revert to normal operation when RC OAT is 1 degC below RC ST If the energy savings option RC OCCesave is Yes AND outside air temperature is below 0 degC then linearly limit damper opening from 100 down to 0 as RC 0CC_PROB goes from 20 down to 0 Note No need to override in extremely warm weather this is handled by the normal economizer function Mixing dampers RC MAD shall go fully closed when supply fan RC SF is OFF OR RC OCCUPIED is No 17 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 15 In order to provide for a consistent interface
29. it would also be possible for the system to control the amount of fresh air introduced into the space Since the mechanical system is designed to bring in the amount of fresh air required for full occupancy energy savings are possible if the number of students is less than maximum NOTE Simple breaks in occupancy are already handled by the energy saving option i e dampers closed and exhaust fan off when no occupancy is sensed If control over fresh quantities is being implemented or considered 1 For reliability reasons it is not recommended that any CO2 control routine increase fresh air quantities above that provided for in the standard mechanical design These are already significant and provide for a fully occupied classroom 22 3 10 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 2 If there is a problem with the sensor i e when RC CO2_FAULT is in alarm disable CO2 control over fresh air quantities and revert to normal fresh air rates Only revert to CO2 controlled operation when the alarm has been manually restored i e the operations staff have corrected the problem 3 Setpoint RC CO2_SP should be conservative A default value of 800 PPM would be reasonable and the classroom should not be allowed to exceed 1000 PPM for any significant duration Only allow setpoints between 750 and 900 It should be remembered that the whole purpose of these advanced high performance modular classrooms is
30. max Max space temp over last 24 hrs degC RT RC AST_24min Min space temp over last 24 hrs degC RT RC RH_24max Max RH value over last 24 hrs RH RT RC RH_24min Min RH value over last 24 hrs RH RT RC CO2_24max Max CO2 value over last 24 hrs PPM R RC CO2_24min Min CO2 value over last 24 hrs PPM R ENGINEERING MAINTENANCE RELATED OBJECTS Alberta Infrastructure Guideline for High Performance Modular Classroom Controls Note R read W write T trend O override C Calibrate A alarm amp limits Objects that are required only if related options have been included Name Description and units Interaction RC SAT Supply Air Temperature AI degC RTCA RC MAT Mixed Air Temperature AI degC RTCA RC OCCS Occupancy Sensor DI On Off RT RC TC Time Clock DI Occupied Unoccupied RT RC OCCMOR Man Occup Override Button DI On Off RWO RC FAULT Mech fault DI flamefail etc Alarm Normal RTA RC SUMP_HI High Sump level Alarm DI Alarm Normal RTA RC HSF Supply Fan continuous run DO On Off RWTO RC EF Exhaust Fan DO On Off RWTO RC H Humidifier control DO On Off RWTO RC HTG_E Heating Enable DO enabled disabled RWTO RC CLG Cooling element DX coil DO On Off RWTO RC CLG_E Cooling Enable DO Enabled Disabled RWTO RC MALM Mechanical Alarm DO Alarm Normal RTA RC HMAD Mixed Air Damper AO RWTO RC HTG_R Heating Reset AO RWTO RC OCCsched Occupancy Schedule Option Yes No RWO RC 0CCtclk Occupancy TimeClock
31. n electronic form l In addition to the hardcopy manuals provide the Operation and Maintenance Manuals in electronic form as follows l O amp M data shall be organized exactly as specified for the hardcopy manuals 2 Data shall be compiled into Adobe portable document format and assembled into as few files as practical NOTE It would be preferable if there were no more than one file per division 3 Include table of contents links that allow direct access to data as per the divider tabs required in the hardcopy manual 22 Provide an O amp M Disk in the form of a CD R Insert in suitable pouch in hardcopy manual 6 Backups Provide two 2 complete system backups each must contain everything necessary to restore the system to full operation should a catastrophic failure occur Also include a jpg gif or dxf version of the graphic display screen that can be used by a host system in the future One package is to be included in the Operation amp Maintenance Manual that will remain in the Manuals cabinet in the portable classroom s mechanical space The remaining package is also to be in the cabinet but in a separate enveloped marked SYSTEM BACKUP TEACHER S GUIDE l This guide pamphlet is to provide casual users such as teachers custodial staff or even students with basic operating information for the user interface smart thermostat It must be written in a clear straight forward manner and be free of acronyms and tec
32. nce Modular Classroom Controls DURULUR General INTENT The intent of this document is to provide guidance regarding the scope installation configuration and programming of the system that will be used to control the mechanical equipment and lighting in a high performance modular classroom It will also cover backups and documentation for operations staff as well as a user guide for teaching staff A major aim of the AI High performance modular classroom Program is to provide students and teachers with classroom units that have a level of indoor air quality and comfort comparable to that of any regular classroom AI has also embraced the concept of Green design and the high performance modular classrooms are being designed and constructed with these initiatives in mind The guideline will deal with the desired control sequences to be used to provide this comfortable environment in an energy efficient manner These will integrate mechanical system control occupancy sensing equipment scheduling as well as lighting override control Additional operational features such as tie ins for a school security system and dial out mechanical alarm will also be detailed A major component of the guideline is to provide a common interface profile based upon BACnet objects to facilitate interfacing various classrooms from differing vendors into a school s EMCS network in a standardized fashion ABBREVIATIONS BACnet ASHRAE Standard Building Au
33. ng each field device IDENTIFICATION Use heat shrink sleeves with printed or legible hand written identifier OR factory coded slip on identification bead markers or sleeves Wrap on adhesive strips are not allowed Size of sleeves to be selected so that they do not slip off when wire is removed from termination and shaken Wiring more than 1 meter in length must be labeled at both ends Labels for all system point wiring shall as a minimum contain the following information l Panel end panel terminal number or hardware address 2 Device end panel number as well as panel terminal number or hardware address Label panel power supply wiring with the panel connector number Label communications port wiring with panel connector number and device name e g Jl modem J2 printer Label communications trunk wiring with the panel number router number etc to which the other end of the cable is connected Wiring on each side of a terminal block or splice shall be labeled with the information required for the device end of the wire 31 6 4 6 5 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls Identify all input sensors and output devices actuators motors and equipment with laminated point tags containing the following information l Logical Point Mnemonic 2 Point Hardware Address and connection terminal identifiers 3 Associated System Identification A Point Description
34. ng style should be of a form that enables the control strategies to be easily followed Clarity simplicity and elegance are more important than program size Extensive inclusion of comments is mandatory Hundreds of classrooms will be constructed a little extra time spent in preparation and documentation will have huge paybacks during warrantee and beyond A Text based programs must be modular in nature and as structured as the language will permit Unconditional branching should be used sparingly All jumps from the body of a module should target the end of that module Similarly jumps from the body of a sub module should target the end of that sub module 5 Graphic style programming must be nested broken into easily manageable modules that can be clearly shown on letter sized sheets Each to be well annotated with text descriptions of the function of each such graphic page Large function blocks should have all parameters listed on accompanying pages 6 The control sequences need to accommodate the following scenarios l Controls completely self contained with occupancy determined by classroom occupancy sensor only When occupancy is sensed lights are enabled and the mechanical system operates in daytime occupied mode When occupancy is no longer being sensed the outside air is slowly decreased to zero after a time delay lights are turned off and the mechanical system is shut down and operated in night setback mode 2 Controls completely
35. nical system These are not specific to actual equipment but are generic in nature These include scheduling occupancy setpoints failure alarms etc Be Engineering objects required to setup features or tune the generic control sequences These include system status setpoint offsets control loop parameters etc 3 Product specific objects options not included above 4 In the following profile descriptions the refers to the classroom number It is expected this portion of the name will need to be changed every time a classroom is relocated and incorporated into a new network Italicized names refer to variables or virtual points BASIC OPERATIONAL OBJECTS Note R read W write T trend O override C Calibrate A alarm amp limits Objects that are required only if related options have been included Name Description and units Interaction RC OAT Outside Air Temperature AI degC RTC RC ST Space classroom Temperature AI degC RTCA RC fRH Space Relative Humidity AI RH RTCA RC CO2 CO2 AI PPM RTC RC LL Light Level AI Lux RT RC L Lighting Contactor DO On Off RWTO RC OCCUPIED Occupied Mode flag Yes No RWTO RC ST_USP User Space Temp Setpoint degC RWTO RC LL_SP Light Level Setpoint Lux RWTO RC ST_24max Max space temp over last 24 hrs degC RT RC AST_24min Min space temp over last 24 hrs degC RT RC HOAT_24max Max OAT over last 24 hrs degC RT RC OAT_24min Min OAT over last 24 hrs degC RT RC ST_24
36. ntly marked removable terminal block for the wiring of all sensors control devices network and PCU power Manual Hand Off Auto override switches for fans gas valves dampers and heat reclaim output points Intelligent thermostat net sensor with the following features as a minimum vl Screen capable of continuous display of operating mode system status as well as outside and inside air temp to a resolution of 0 5 degC 2 Four programmable buttons providing setpoint increase decrease and occupied unoccupied mode operation 3 Additional keys and screen display functionality as required to provide access to setup and sequence configuration functions Entry into setup mode shall be protected with some form of pass code 4 Ability to set device to continuously display room setpoint or current room temperature 5 Space temperature accuracy of 0 3 degC 6 Neutral colour vented metal or robust plastic enclosure with base to cover wall opening Each physical or virtual point controller point or schedule is to have a unique user definable system wide logical point mnemonic The format of these point mnemonics shall conform to the Alberta Infrastructure Guideline for Logical Point Mnemonics Refer to control sequences for other relevant names PROGRAMMING CONFIGURATION TOOL AND MANUALS One licensed software development tool must be provided with every classroom to allow the creation modification configuration saving reloadin
37. nual override is active OR RC OCC_PROB gt 30 occupancy sensor has had 1 capture OR RC H OCCUPIED is Yes AND RC OCCesave is No OR RC OCCUPIED is Yes AND RC OCCesave is Yes AND RC L_INTMR is OFF i e not trying to pulse lights off for 1 sec Then enable RC L i e allow lights to be turned on Else disenable RC L turn lights off NOTE This routine must be scanned very rapidly to ensure lights can be pulsed off properly or some other equivalent logic must be created to achieve the same result If daylight harvesting is to be used then modulate appropriate classroom lights to maintain light level RC LL at a setpoint RC LL_SP adjustable from the intelligent thermostat s keypad Control should be reasonably rapid but time averaged so as not to be annoying during fluctuations in daylight caused by cumulous clouds or the like EMERGENCY CONTROL On detection of failure of intelligent thermostat Supply fan shall go into continuous operation Exhaust fan shall remain off occupied or unoccupied mode Mixing dampers shall remain fully closed occupied or unoccupied mode Space temperature to be controlled using the mixed air temperature sensor Lighting control is to remain unaltered UPLNE 21 3 9 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls CO2 MONITORING AND CONTROL Each classroom is to be equipped with a carbon dioxide sensor RC COZ2 that pro
38. ontinuously above 33 for 10 minutes AND the time is between 6 00AM and 9 00PM Then set RC OCCUPIED to Yes Else If RC OCC_TMR 0 i e occupancy manual override is not active OR RC 0CCtclk is Yes AND input RC TC shows unoccupied OR RC 0CCiclk is No AND RC OCCschd is Yes AND schedules are showing an unoccupied state OR RC 0CCiclk is No AND RC OCCschd is No AND RC OCC_PROB lt 1 OR the time is NOT between 6 00AM and 9 00PM Then set RCH OCCUPIED to No i e The classroom goes into occupied mode if the manual override timer is active OR the time clock option is enabled and the time clock contact is made OR the time clock option is not enabled but the internal schedules are active and showing an occupied state OR occupancy is being determined solely via the occupancy sensors and these have been indicating at least some occupancy over 10 minutes and the time of day is reasonable Otherwise the classroom goes into unoccupied mode if the manual override timer is not active OR the time clock option is enabled but the time clock contact is open OR the time clock option is not enabled but the internal schedules are active and showing an unoccupied state OR occupancy is being determined solely via the occupancy sensors and these have not seen anything for many minutes or the time is outside serviced hours 15 3 6 Alberta Infrastructure Guideline for High Performance Modular Class
39. outside air temperature RC ST_24max Maximum classroom space temperature RC ST_24min Minimum classroom space temperature RC RH_24max Maximum classroom relative humidity AR WN 13 3 5 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 6 RC ARH_24min Minimum classroom relative humidity 7 RC CO2_24max Maximum classroom CO2 level 8 RC CO2_24min Minimum classroom CO2 level DETERMINATION OF OCCUPANCY Occupancy sensors are to be dual technology IR UV IR Ultrasonic etc Select devices specifically designed for this application The output contact should turn ON when either one of the sensor technologies is activated but should turn OFF only when both technologies are indicating off not just one of the two Determination of occupancy is simple when time schedules or a time clock are available However in self contained mode or whenever the energy savings option is active occupancy can only be determined via motion sensors mounted near the windows and sensing into the room In practice it has been difficult to find a balance between responsiveness and nuisance activations One wishes to avoid going into fully occupied mode should someone just look into the room but it should not require there to be 10 people moving about the room either The first indication of occupancy must enable the lights but more activations should be required to bring on the mechanical systems The strategy should cov
40. profile for a variety of mechanical systems a modulating heating element has been assumed such that 0 indicates no heat and 100 is for full heat If a fully modulating heating element has been provided then RC HTG would be an actual analogue output point for all other heating methodologies control the actual hardware outputs based upon the value contained in a virtual point RC HTG Many scenarios also require enable disable control over the heating device via RC HTG_E Some examples of likely possibilities follow Al For a PCU controlled fully modulating device such as pulse width modulated electric heating RC ST_CO 0 45 RC ST_CO 50 or more 40 or less RC HHTG 100 full heat 0 no heat RC HTG_E heating device disabled heating device enabled For a PCU controlled modulating gas valve with a 4 1 turn down ratio RC ST_CO 0 35 RC ST_CO 40 or more 30 or less RC HTG 100 full fire 0 minimum fire i e 25 output RC HTG_E heating disabled heating enabled For four stages of heating a separate digital output is required for each stage RC HTG becomes a virtual point related to the stages as follows RC AST_CO RC HTG 0 11 11 22 22 33 33 44 Heating Stage 75 100 Stage 4 ON 98 OFF 77 50 75 Stage 3 ON 73 OFF 52 25 50 Stage 2 ON 48 OFF 27 0 25 Stage 1 ON 23 OFF 2 For two stages of heating a separate digital output is r
41. rchitecture 3 System Schematics A PCU Configuration Provide a basic configuration diagram showing PCU and related devices Provide an explanation of system architecture Describe each hardware component and the networks that manage system communications System Schematics Provide schematics of the mechanical system indicating point locations mnemonics and hardware address Include any wiring details and equipment schematics showing where and how equipment is interfaced to PCU Drawings must be clear and of adequate size for easy reading If necessary fold larger sheets into binder 24 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 5 PCU Provide a copy of the PCU panel directory showing point mnemonics termination addresses and wiring numbers Also include the panel directory of any associated equipment interface cabinet 3 Controls Software Database Programming Al Organize the information into sections with index and divider tabs as follows l Point object Tables 2 Graphics 3 Descriptions and Procedures A PCU Point object Tables Provide two lists that when combined contain all the physical and virtual points objects as well as a suitable description as to their function and their database address The first table is to contain only the standard profile objects the second to contain all remaining objects Graphics Provide a hardcopy of recommended graphic display scr
42. required to preserve lamp life under frequent switching Mechanical and electrical requirements must be coordinated with the mechanical and electrical disciplines Standard Functional Profile GENERAL The ultimate purpose of a high performance modular classroom is to allow it to be moved from one site to another with little difficulty Since it is expected that classrooms will be sourced from a variety of manufacturers and will be supplied with different mechanical systems it is necessary to ensure that the controls appear the same from one classroom to another in as much as this is possible Without such standardization significant unnecessary expense is added to a move BACnet has been chosen as the interface standard mainly because all previous high performance modular classrooms have included native BACnet compliant hardware However a major benefit of BACnet is that it allows auto discovery of connected hardware and exposed objects Integration of a high performance modular classroom to a school s EMCS is greatly facilitated if the exposed objects follow a common naming convention and offer identical functionality Consistency of common features is mandatory For the purposes of this guideline these objects will be broken down into three types 2 2 2 3 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls l Basic operational objects required for day to day operation interaction with the mecha
43. room Controls PACKAGED HVAC UNIT CONTROL DETAILS Calculate the space temperature setpoint value RC ST_SP as follows l In occupied mode when RC OCCUPIED is Yes let the operating setpoint RC AST_SP be the user set value RC ST_USP which is limited to a range between RC ST_SPmin and RC ST_SPmax 2 In unoccupied mode when RC OCCUPIED is No let the operating setpoint equal the night setpoint RC ST_NSP but limited to values between 15 and 20 degC RC ST_NSP is to have a default value of 17 degC RC ST_NSP must not be allowed to be higher than RC ST_USP Supply fan RC SF is to run continuously in occupied mode when RC OCCUPIED is Yes In unoccupied mode the fan is only to run as necessary to maintain space at the setback setpoint No more than 6 cycles per hour are to be allowed i e minimum off time is to be about 10 minutes Exhaust fan RC EF is to run while RC OCCUPIED is Yes AND supply fan RC SF is running AND mixing dampers RC MAD are greater or equal to minimum position RC MAD_MIN Exhaust fan RC EF is to be OFF while RC OCCUPIED is No OR supply fan RC SF is OFF OR mixing dampers RC MAD are less than 1 2 of minimum position RC MAD_MIN Minimum off time is to be 10 minutes Use controller RC ST_CO to sequence heating mixing dampers and cooling stages as follows RC AST_CO controller output 0 45 75 10
44. rs at full return air Bias Set at 0 Controlled variable Space temperature RC MAT Setpoint RC AMAT_SP Parameter RCH MAT_PG Proportional gain default value equiv to 25 degC error Parameter RCH MAT_IG Integral gain default value equivalent to 5 degC error hour Miscellaneous integral windup to be limited Parameter RC HR_DFRSTdur Heat reclaim defrost cycle duration units Minutes default value of 10 minutes Parameter RC HR_DFRSTper Heat Reclaim defrost cycle period units Hours default value of 8 hours Variable RCH HR_DFRST Heat reclaim in defrost mode units Yes No default value of No Interrupt timer RC L_INTMR Lighting Interrupt Timer units On Off default value is Off This timer is to turn On for one second every time probability RC OCC_PROB drops below 20 It resets after the one second activation and waits until the probability value once again goes above 20 then activates again whenever the probability value passes down through 20 Variable RC DTIME Decimal Time units Hours This is the value of PCU time in decimal hours in 24 hour format It can be used to check PCU clock synchronization communications issues etc BASIC DATA GATHERING Create routines that provide the following maximum and minimum values over a sliding window period of the last 24 hours hourly data is sufficient RC OAT_24max Maximum outside air temperature RC OAT_24min Minimum
45. s Yes AND input RC TC shows unoccupied OR RC O0CCschd is Yes AND schedules are showing an unoccupied state Then limit RC OCC_PROB to values between 0 and 33 If RC OCC_TMR gt 0 i e occupancy manual override is active Then set RC OCC_PROB to 33 Parameter RC ST_SPmax Maximum allowed Space Temp SetPoint units DegC default value of 25 0 entry limited to values between 23 and 32 Parameter RC ST_SPmin Minimum allowed Space Temp SetPoint units DegC default value of 21 0 entry limited to values between 17 and 22 Variable RC ST_USP Space Temp User SetPoint units DegC default value of 22 5 DegC This is the value of space temperature setpoint entered or adjusted by the user via the intelligent stat keypad Controller RC AST_CO Space temperature control loop output units Output Range 0 100 but limited to 0 75 if RC CLG_INSTALLED is No Bias Set at 45 12 3 4 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 16 17 18 19 20 21 Controlled variable Space temperature RC ST Setpoint RC ST_SP Parameter RC ST_PG Proportional gain default value equivalent to 25 degC error Parameter RC ST_IG Integral gain default value equivalent to 5 degC error hour Miscellaneous integral windup to be limited Controller RC MAT_CO Mixed air temp control loop output units Output Range 0 100 0 is for dampe
46. s together with a description and examples of their use in programming 29 6 1 6 2 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls Execution OCCUPANCY AND LIGHT SENSORS DEVICES Install TWO occupancy sensors contacts wired in parallel Sensors to be mounted high in back corners near the windowed wall Sensor beams should cross and cover both possible blackboard locations Sensing area must not include windows ceiling or door out to hallway Sensitivity to be adjusted so as to trigger on student or teacher movement but not to respond to normal heating ventilating air conditioning system warm or cold air movement A single 360 degree dual technology ceiling mounted device may be considered if its performance can meet these requirements If daylight harvesting is to be used then have light sensors look down from ceiling in area that receives light from the windows clearstory or other opening a For a generic design light sensors would be located approximately 3m in from the windows For a clearstory or light tube sensor should point down from ceiling in close proximity to lit area 2 Lighting control zones to be coordinated with sensed areas 3 Some form of daylight attenuation may be required if class is to be able to be darkened for AV presentations These may be manual in nature WIRING AND INSTALLATION Wiring to CSA C22 2 No 75 M1983 copper conductor 600 V RW90 X link insulation
47. tomation amp Control Network Protocol CCS Central Control Station EMCS Energy Management Control Systems PCS Portable Control Station PCU Programmable Control Unit PID Proportional Integral Derivative BASIC MECHANICAL amp ELECTRICAL REQUIREMENTS The mechanical system is to include an exhaust fan to ensure positive entry of 212 L s of fresh air heating with minimum 4 1 turndown 2 1 if heat reclaim is provided humidifier small sump and sump pump c w high level alarm 100 outside air free cooling capability UPLNE 2 1 Alberta Infrastructure Guideline for High Performance Modular Classroom Controls 6 mixing dampers for non displacement systems T heat reclaim and CO2 sensor System must be designed and component sizing selected such that temperature swing during any form of cycling operation under any heating cooling or ventilation mode is less than 5 degC Include room for DX cooling and all necessary controls and programming for this function whether or not classroom is being equipped with cooling System must be designed such that there are no marked changes in classroom pressurization under any combination of supply fan speed damper position or exhaust fan operating status A contactor is required for overall control of the lighting If daylight harvesting is being employed then additional controls or control interfaces will be required Ensure these are compatible with the PCU Program start ballasts are
48. vides the concentration of CO2 in parts per million PPM Inexpensive CO2 sensors may drift over time Select stable electrochemical devices that are guaranteed accurate for at least 3 years or ensure devices have some form of auto zero self calibration function Even then the devices should be checked annually until some confidence in their reliability is attained Sensors must be able to be checked and calibrated by operations staff Devices that need to be sent out for calibration are not recommended If special software and or cables are required for calibration provide supplier s data in the O amp M Manual along with retail costs Provide a sequence of operation that checks the minimum value of the sensor over a 24 hr period The sliding window minimum value of CO2 level from the basic data gathering routines can be used for this check If the lowest value over the last day has not been near the atmospheric average then there is likely a problem with the sensor so alarm the situation i e At 10 00 AM IF RC CO2_24min is NOT between 250 and 500 THEN set RC CO2_FAULT to alarm and display this condition on the stat Once the fault has been corrected a manual reset of RC CO2_FAULT must also restore RC CO2_24min to 499 so as to allow further collection of data starting at a normal value As a minimum CO2 must be monitored However with the level of controls necessary to produce the sequences of operation in this guideline
Download Pdf Manuals
Related Search