Optimal Start Attributes - Metasys - LIT-1201793 - Software Application - Site Management Portal - 12.0.50

Metasys Site Management Portal Help

Brand
Metasys
Product name
Site Management Portal
Document type
User Guide
Document number
LIT-1201793
Version
12.0.50
Revision date
2023-06-02
Language
English

This object contains attributes common to many Metasys system objects. These common attributes are described in the Common Object Attributes section. This section includes attributes of the Focus/Configuration tab, the Diagnostics tab (if applicable), and any other tab specific only to this object. See the Object and Feature Tabs section for information on the attributes that appear on the other tabs of this object (for example, the Hardware and Options tab appear on point objects).

Note: In the Notes column, letters indicate the following: In the notes column, letters indicate the following: C - Configurable, R - Affected by Extension’s Reliability, W - Writable.
Table 1. Optimal Start Object Attributes - Focus/Configuration Tab

Attribute Name

Notes

Initial Value

Values/Options/

Range

Description

Adaption Enabled

C,W

True

 

Indicates whether OST uses adaptive learning to change the building heating and cooling constants and heating and cooling deadtimes.

Calc Prestart Date

     

Indicates the last calculated prestart date. This value is updated each time the optimal start time is calculated (between early start time and optimal start time).

Cal Prestart Time

     

Indicates the last calculated prestart time. This value is updated each time the optimal start time is calculated (between early start time and optimal start time).

Calc Prestop Date

     

Indicates the last calculated prestop date. This value is updated each time the optimal stop time is calculated (between early stop time and optimal stop time).

Calc Prestop Time

     

Indicates the last calculated prestop time. This value is updated each time the optimal stop time is calculated (between early stop time and optimal stop time). If Max Prestop Time is zero, the value of this attribute is equal to the unoccupied time.

CoolDown Command

W

1

Set redirected to ZWC States Text; Number of States redirected to ZWC Nbr States

Only available in the online UI

Specifies the command sent to the Zone WC Mode Obj point at prestart time when in cooling mode. The enumeration set and number of states for this attribute are redirected and filled in at runtime from the Zone WC Mode Obj point. The default value is set to a value of 1 upon creation so the attribute requires no configuration.

Cooling Constant

C,W

75.0

1–999

Defines the rate at which the zone cools down after equipment startup. If adaptation is enabled, this constant is adapted without user intervention. If adapting and the OST object Cooling Setpoint and Heating Setpoint attributes reference the same object on a field controller, then the cooling constant is adapted even if the mode is not cooling, meaning both constants change.

Cooling Dead Time

C,W

10 minutes

1–480

Units = Minutes

Indicates the time required after startup to lower the temperature by one degree. This value is adapted by the OST algorithm, if adaptation is enabled. If adapting, cooling, and heating setpoints are the same attribute, the Cooling Deadtime is adapted even if the mode is not cooling, meaning both deadtimes change.

Cooling Design Temp

C,W

35.0 deg C or 95.0 deg F

-20 to 120

Units = Temperature Units

Indicates the highest outside temperature at which the cooling system maintains zone comfort in the cooling mode.

Cooling Setpoint

C,W

   

Identifies the attribute of an object used to define the zone occupied target cooling temperature. This attribute may be the same as the Heating Setpoint attribute.

Cooling Stpt Status

   

Offline = 0

Online = 1

Uses Offline Online (Set 91).

Identifies the OST object’s connection status to the Cooling Setpoint attribute. If this status is Offline, the Present Value is set to Not Operational.

– Offline: Cooling Setpoint attribute is offline.

– Online: Cooling Setpoint attribute is online.

Display Precision

C,W

0.1

Uses Display Precision (Set 0).

Indicates the rounded position and decimal places to display for this object.

Heating Constant

C,W

75.0

1–999

Defines the rate at which the zone heats up after equipment startup. If adaptation is enabled, this constant is adapted without user intervention. If adapting and the OST object Cooling Setpoint and Heating Setpoint attributes reference the same object on a field controller, then the heating constant is adapted even if the mode is not heating, meaning both constants change.

Heating Deadtime

C,W

10 minutes

1–480

Units = Minutes

Indicates the time required after startup to raise the temperature by one degree. This value is adapted by the OST algorithm, if adaptation is enabled. If adapting, cooling, and heating setpoints are the same attribute, the Heating Deadtime is adapted even if the mode is not heating, meaning both deadtimes change.

Heating Design Temp

C,W

-20.6 deg C or -5.0 deg F

-35 to 90

Units = Temperature Units

Indicates the lowest outside temperature at which the heating system maintains zone comfort in the heating mode.

Heating Setpoint

C,W

   

Identifies the attribute of an object used to define the zone occupied target heating temperature. This attribute may be the same as the Cooling Setpoint attribute.

Heating Stpt Status

   

Offline = 0

Online = 1

Identifies the OST object’s connection status to the Heating Setpoint attribute. If this status is Offline, the Present Value is set to Not Operational.

– Offline: Heating Setpoint attribute is offline.

– Online: Heating Setpoint attribute is online.

Max Prestart Time

C,W

120 minutes

5–480

Units = Minutes

Indicates the maximum period of time required to bring the zone up to occupancy setpoint temperature under the worst conditions (earliest optimal start time).

Max Prestop Time

C,W

0 minutes

0–60

Units = Minutes

Indicates the maximum period of time that the heating/cooling system can be shut down and still maintain the occupied zone temperature until entering the unoccupied mode (earliest optimal stop time). By setting this time to zero (the default value), optimal stop is disabled.

Min Prestart Time

C,W

20 minutes

0–240

Units = Minutes

Indicates the minimum period of time before occupancy to start the heating/cooling system. This time allows for the required amount of air changes in the zone prior to occupancy (latest optimal start time).

OST Type

C,W

Heating/Cooling

Heating and Cooling = 0

Heating Only = 1

Cooling Only = 2

Uses OST Type (Set 126).

Defines the OST supported configuration. When the zone is in a mode not supported by the OST object, the Present Value is idle. OST-supported modes include:

– Heating and Cooling

– Heating Only

– Cooling Only

Outdoor Air Temp

C,N,W

   

Identifies the attribute of an object used to determine the outdoor temperature:

– If this attribute is not defined, or is offline, the outdoor air temperature is not used in the OST calculations and is assumed to be within the design temperatures.

– If an Analog attribute reference is defined for the outdoor air temperature, it aids in determining if the Optimal Start object should adapt constants and deadtimes.

– If the attribute is defined and outside the design temperatures, deadtime and constant calculations are skipped.

– If the attribute is defined and is outside the design temperatures during Prestart, the optimal start time is set to early start time.

– If the attribute is defined and outside the design temperatures during Prestop, do not Prestop.

Present Value

D

Idle

Idle = 0

Prestart Heating = 1

Prestart Cooling = 2

Calculating Deadtime = 3

Calculating Constant = 4

Occupied = 5

Prestop = 6

Not Operational = 7

Uses OST State (Set 125).

Represents the current value of the object:

– Idle: Waiting for next occupied time for a supported mode (heating or cooling).

– Prestart Heating: Heating optimal start time is pending.

– Prestart Cooling: Cooling optimal start time is pending.

– Calculating Deadtime: Valid only if Adaptation Enabled.

– Calculating Constant: Valid only if Adaptation Enabled.

– Occupied

– Prestop: Waiting to reach optimal stop time. If Max Prestop Time = 0, then mode is Occupied, not Prestop.

– Not Operational: Optimal Start object is not operational due to errors in its connection status to other required objects. The specific problem can be determined by viewing the other status attributes. The Optimal Start object could also be Not Operational (or Unreliable) if the Zone Occ Mode Obj is in the schedule but there are no valid start and stop times for that day (due to holiday or schedule offline, for example).

Prestart Cooling Command

W

1

Set redirected to zone occupied mode (ZOM) States Text; Number of States redirected to ZOM Nbr States

Only available in the online UI

Specifies the command sent to the Zone Occ Mode Obj point at prestart time when in cooling mode. The enumeration set and number of states for this attribute are redirected and filled in at runtime from the Zone Occ Mode Obj point. The default value is set to a value of 1 upon creation so the attribute requires no configuration.

Prestart Heating Command

W

1

Set redirected to ZOM States Text; Number of States redirected to ZOM Nbr States

Only available in the online UI

Specifies the command sent to the Zone Occ Mode Obj point at prestart time when in heating mode. The enumeration set and number of states for this attribute are redirected and filled in at runtime from the Zone Occ Mode Obj point. The default value is set to a value of 1 upon creation so the attribute requires no configuration.

Prestop Command

W

0

Set redirected to ZOM States Text; Number of States redirected to ZOM Nbr States

Only available in the online UI

Specifies the command sent to the Zone Occ Mode Obj point at prestop time. The enumeration set and number of states for this attribute are redirected and filled in at runtime from the Zone Occ Mode Obj point. The default value is set to a value of 0 upon creation so the attribute requires no configuration.

Relative Temp Units

C

Relative deg F

Uses Unit Set (Set 869).

Specifies the units associated with the Temp Differential attribute.

Reliability

 

Reliable

Uses Reliability (Set 503).

Indicates if a value is questionable due to operational errors in the Optimal Start object’s connection status to other required objects. Without a valid start and stop time for the current day (due to holiday or schedule offline, for example), the value is also Unreliable.

Schedule Occupied Command

W

1

Set redirected to ZOM States Text; Number of States redirected to ZOM Nbr States

Only available in the online UI

Specifies the command sent to the Zone Schedule Obj point at prestart time when in occupied mode. The enumeration set and number of states for this attribute are redirected and filled in at runtime from the Zone Schedule Obj point. The default value is set to a value of 1 upon creation so the attribute requires no configuration.

Schedule Unoccupied Command

W

0

Set redirected to ZOM States Text; Number of States redirected to ZOM Nbr States

Only available in the online UI

Specifies the command sent to the Zone Schedule Obj point at prestart time when in unoccupied mode. The enumeration set and number of states for this attribute are redirected and filled in at runtime from the Zone Schedule Obj point. The default value is set to a value of 0 upon creation so the attribute requires no configuration.

Send OK

     

Indicates if the status of the last command was sent to the Zone WC Mode Obj, Zone Occ Mode Obj, or Zone Schedule Obj.

Stpt Reached Time

     

Indicates the time at which the zone temperature was equal to (within differential) the zone setpoint. This point is set between the optimal start time and occupied. If this point is not reached during that time, then it continues to be monitored during the occupied time until the zone temperature reaches the setpoint.

Temp Differential

C,W

3.0 delta deg F or 1.67 delta K

0–10

Units = Relative Temp Units

Indicates the value added and subtracted to the zone setpoint to define a temperature range.

Temperature Units

C

Deg F

Uses Unit Set (Set 869).

Indicates the units associated with the attributes for temperatures.

Warmup Command

W

1

Set redirected to ZWC States Text; Number of States redirected to ZWC Nbr States

Only available in the online UI

Specifies the command sent to the Zone WC Mode Obj point at prestart time when in heating mode. The enumeration set and number of states for this attribute are redirected and filled in at runtime from the Zone WC Mode Obj point. The default value is set to a value of 1 upon creation so the attribute requires no configuration.

Zone Occ Mode Obj

C,W

   

Identifies the object used to command a zone to occupied or unoccupied. This object must be specified in the Zone Schedule Obj. This is commanded by scheduling to occupied and by OST if prestop is enabled.

If the Zone Occ Mode Obj and the Warmup/Cooldown Mode Obj are the same point, then the point is commanded by Scheduling at the scheduled time.

Zone Occ Time

     

Indicates the scheduled zone occupied time, obtained from the Zone Schedule Obj.

Zone Schedule Obj

C,W

   

Identifies the Schedule object, which schedules the Zone Occ Mode Obj. This object must be defined in the schedule and have valid start and stop times for the current day in order for OST to run. Otherwise, the OST object’s Present Value is Not Operational. Only one Start and Stop time can be defined per day, and the Start time must precede the Stop time. The Start time must be defined as binary State ON (1) and Stop time must be defined as binary State OFF (0).

Zone Schedule Status

   

Offline = 0

Online = 1

Identifies the OST object’s connection status to the Zone Schedule Obj. If this status is Offline, the Present Value is set to Not Operational.

– Offline: Zone Schedule Obj is offline

– Online: Zone Schedule Obj is online.

Zone Temperature

C,W

   

Identifies the attribute of an object used to determine the zone temperature.

Zone Temp At Start

N

   

Specifies the zone temperature at the last optimal start time.

Zone Temp Status

   

Offline = 0

Online = 1

Identifies the OST object’s connection status to the Zone Temperature attribute. If this status is Offline, the Present Value is set to Not Operational.

– Offline: Zone Temp attribute is offline.

– Online: Zone Temp attribute is online.

Zone Unocc Time

     

Indicates the scheduled zone unoccupied (vacancy) time, obtained from the Zone Schedule Obj.

Zone WC Mode Obj

C,W

 

Must be defined as an N2 BO, BV, MO, or MV object.

Identifies the object used to command a zone to Warmup or Cooldown mode. This object may be the same as the Zone Occ Mode Obj. This object is commanded by the OST at the optimal start time. This object is released at the occupied time unless this object is also the value for the Zone Occ Mode Obj.