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Schedule is a concept of defining the usage of a building during the day of the week based on the occupancy of the building, and determining the HVAC needs for the corresponding occupancy.
Below is a schedule from the portal.
From above it is evident that a schedule is just like any other schedule, time table or a planned timed session, but in our case the schedule does not only have a defined time limit, for which the building will be occupied for the day, but it also has a defined setpoint for each day of the week which determines the load on the HVAC equipment.
|Types of Schedules
There are 3 types of schedules
Zone Schedule - It is a defined time limit with a defined setpoint, which is set up for a particular zone. This defines the occupancy of the zone for day in a week, and the load on the module level HVAC equipment. This allows users to have local control of their temperature. Zone schedules should always be within the building schedule and are editable via the zone tab on the CCU or Facilisight application.
Below is a zone schedule from the portal.
When a change is made to the desired temperatures in the zones following a zone schedule, via the CCU/Portals/Apps /smart devices, the change get updated in the zone schedule immediately, and the zone schedule holds the new desired temperature indefinitely until a new change is made.
Below is a change made to the desired temperature from the portal for the zone schedule specified above.
Below is the change updated in the zone schedule in the portal.
The change gets updated in the CCU as well.
Building Schedule - Enforces consistent temperature scheduling over multiple zones in a single building. Users have temporary overrides for temperature that are only good till the end of the current occupied time. The building schedule can be edited from the CCU or via Facilisight using the buildings tab.
Below is a building schedule from the portal.
When a change is made to the desired temperatures in the zones following a building schedule, via the CCU/Portals/Apps /smart devices, the change in the desired temperature does not reflect in the schedule section, but the new desired temperature will be in effect till the end of the current occupied time only.
Below is a change made to the desired temperature from the portal for the building schedule specified above.
Below is when the change made is reverted post the end of the schedule hours from the portal, to the desired temperatures specified as per the above shown building schedule.
For more information refer to Setting Building & Zone Schedule from Facilisight & CCU
Intrinsic Schedule- A schedule which is introduced in the Algorithmic level, and not a configurable option, which shortens the actual building schedule, based on the statuses of the individual zones, using any system level device (AHU's & RTU's). for more information refer Intrinsic Schedules for System Profiles
Named schedule- is a type of schedule that is introduced in the 75F system to make life easier for the Facility and the Organization managers. Being an organization manager who handles the BMS for multiple buildings, or a facility manager who handles many zones in a building, it was really a tedious and time consuming task to go and add or update the zone schedules for the individual zones in the each and every building handled. With the introduction of the Named Schedule in the 75F system, the organization manger is able set schedules for individual zones in multiple buildings, with just a selection from a dropdown, and when there is a change in the set schedule, making the change in the named schedule created, will update the change in all the places the schedule is applied in. for more information refer Creating & Editing Named Schedule
Special Schedule is a schedule which allows a Facility manager to introduce a schedule which is outside of the actual set of building and zone schedules. For example, a Facility manager would want to schedule the building on a Saturday for a small duration of time for which he would want the building HVAC equipment to run. A schedule like this on a Saturday which is outside of the actual building schedule has been made possible with the introduction of Special Schedule. For more information refer Creating Special Schedules from CCU, Creating Special Schedule from Portals & Apps
|Modes of Occupancy Based on Schedule
The 75F BMS implements several modes to account for how the building is used and the associated HVAC needs based on the schedule set:
Occupied (Setpoint) Mode:
When the system is in occupied mode the system will try to maintain all desired temperatures and try to keep the system's comfort index within the selected comfort select or value. During occupied mode, the system can only perform actions based on the mode it is in. If it is in auto mode, the system will automatically switch between cooling and heating. If the system is in heat or cool only the system will only take action when heating or cooling is necessary. If IAQ (Internal Air Quality) control is enabled, the system will maintain those thresholds.
Auto Away Mode:
If occupancy detection (using the PIR sensor) is enabled, and no occupancy is detected during the occupied part of the schedule, then the temperature is setback by the autoAwaySetback tuner.
Unoccupied (Setback) Mode:
During unoccupied mode the system will begin to allow the temperatures to drift to the setback temperatures. This unoccupied mode is used to help save energy by letting the building drift more naturally to a lower or higher temperature depending on the environment. The temperature setback amount is determined by the unoccupiedSetback. No IAQ (Internal Air Quality) is maintained during this period .
Forced Occupied (Temporary Hold) Mode:
A zone enters Force occupied mode when a user interacts to change a temperature control (Local interface sensor or user app or via the Facilisight application) during unoccupied mode and physically sets a desired temperature. For Standalone equipment, the zone will independently actuate the equipment as needed/allowed to drive desired temperatures. Zone will be given a temporary priority of forcedOccupiedpriority for forcedoccupiedtime during the forced occupied trigger. For central equipment, IAQ (Internal Air Quality) is maintained if enabled.
Auto forced Occupied Mode:
Auto forced occupied mode is same as the forced occupied mode the only difference is Auto forced occupied mode is triggered for occupancy, which is detected due to a occupancy sensor that detected the occupancy in the room or the zone.
It is the mode which is triggered when the building is about to be occupied. The algorithm constantly views how far apart the desired and current temperatures are. The algorithm knows when every zone is going to be occupied based on the schedule, and is aspiring to reach that temperature. There are tuners for heatingPreconditioningRate and coolingPreconditioningRate that determines the number of minutes per degree difference between desired and current temperature the system should start heating or cooling to meet the needs of the building by the occupied time. No IAQ (Internal Air Quality) is maintained during this period since the building is not expected to have occupants during this time.