Room Light Control
The Room Light Control (RLC) allow controlling the lighting of rooms according to their occupancy and illuminance.
Occupancy Sensors
One or multiple occupancy sensors allow reducing or completely turn off the lighting of a room in response to its occupancy state. The occupancy sensors determine the Occupied state of the room.
Related BACnet properties: Occupancy_Variable_Value.
Occupied Mode
The Occupied Mode is normally written twice each day to enable and disable the Override Timeout. When the Occupied Mode is Ocuppied the Override Timeout is disabled. When the Occupied Mode is Unoccupied the Override Timeout is enabled. It is possible for changes to the Occupied Mode to automatically execute or not the Occupied and Unoccupied commands.
Related BACnet properties: Occupied_Mode, Occupied_Mode_Command_Enable, Override_Timeout, Occupied_Command_Command, Occupied_Command_Value, Unoccupied_Command_Command, Unoccupied_Command_Value.
Occupied Command
When the room enters in Occupied state, the Occupied command is executed. When using a direct value as the command, the command is inhibited if the command value is lower than the current output value.
Related BACnet properties: Occupied_Command_Command, Occupied_Command_Value, Occupancy_Variable_Value.
Unoccupied Command
When the room enters in Unoccupied state, the Unoccupied command is executed. When using a direct value as the command, the command is inhibited if the command value is greater than the current output value.
Related BACnet properties: Unoccupied_Command_Command, Unoccupied_Command_Value, Occupancy_Variable_Value.
Unoccupied Warning
When the room enters in Unoccupied state, a Warning command can be executed. This allows the occupant of the room to be warned that the light might soon go off. During the Warning Time, the occupant can move to return to the Occupied state and the Occupied command is executed. If a wall switch is available in the room, the occupant can press the button to end the Warning Time. When using a direct value as the command, the command is inhibited if the command value is greater than the current output value.
Related BACnet properties: Warning_Time, Warning_Command_Command and Warning_Command_Value, Occupancy_Variable_Value.
Override Timeout
When the Occupied Mode is in Unoccupied mode, it is possible for a button or a network command to temporarily override the level of light of the room. When a command that directly affect the light level of an output of the room, a timer is started. When the timer is elapsed, the room returns to Unoccupied and the Warning and the Unoccupied commands are executed.
Related BACnet properties: Override_Timeout, Occupied_Mode, Warning_Command_Command, Warning_Command_Value, Unoccupied_Command_Command and Unoccupied_Command_Value.
Ignore Time
Once the occupancy state changes to unoccupied the ignore time is used to temporarily ignore the changes to occupied of the occupancy sensors.
Related BACnet properties: Ignore_Time, Occupancy_Variable_Value.
Hold Time
The occupancy state remains occupied for the hold time when the occupancy sensors transition to the unoccupied.
Related BACnet properties: Hold_Time, Occupancy_Variable_Value.
Occupancy Process
One or multiple occupancy sensors allow reducing or completely turn off the lighting of a room in response to its occupancy state.
Related BACnet properties: Occupancy_Variable_Value, Occupied_Mode, Override_Timeout, Occupied_Mode_Command_Enable, Occupied_Command_Command, Occupied_Command_Value, Warning_Command_Command, Warning_Command_Value, Unoccupied_Command_Command, Unoccupied_Command_Value, Ignore_Time and Hold_Time.
- Ignore Time (motion detected)
- Room is occupied
- Hold Time (no motion detected)
- Unoccupied Warning
- Room is unoccupied
Light Sensors
The light sensors are devices that read the current illuminicense and make this value available to the Room Light Control.
Related BACnet properties: Controlled_Variable_Value.
Setpoint
The setpoint is the desired light illuminance of the room. Different setpoints can be used depending on the occupancy state of the room.
Related BACnet properties: Setpoint_Occupied and Setpoint_Unoccupied.
Daylight Harvesting
The daylight harvesting systems use daylight to compensate for the artificial electric lighting needed to properly illuminate a room. Daylight harvesting strategies help reduce energy consumption.
Related BACnet properties: Controlled_Variable_Value, Setpoint_Occupied and Setpoint_Unoccupied.
Multiple Lighting Zones
The multiple lighitng zones functionality allows managing two separate lighting zones within a single Room Light Control. Typically, the Output 1 zone is situated towards the interior of the building, while the Output 2 zone is closer to the windows. Depending on the level of natural light entering the room, the Output 1 zone may need to be brighter to maintain even illumination across the space.
The configuration property Lamp_2_Offset, allows to set the maximum variance between the two lighting zones. The Lamp_2_Limit property determines the light level at which the output values for both zones become the same.
In this example, the Lamp_2_Offset is set to 45, and the Lamp_2_Limit is set to 75.
Demand Response
The demand response allows to limit the level of light of the room.
Related BACnet properties: Demand_Response_Value.
Web Interface
Room Light Control
This page list all the available Room Light Control. It also indicates the current states of the occupancy, light sensors and outputs.
Room Light Control Configuration
This page allows configuring a Room Light Control. Refer to the associated BACnet Loop object for more information about the different parameters.
Room Light Control States
This page displays the internal states and timers of the Room Light Control, providing valuable insights into the operations and status of the Room Light Control, aiding understanding of its functioning.
BACnet Interface
To visualize the states and configure the Room Light Control, use the Loop objects.
The properties of the Loop objects are also available via the objects; Analog Value - Room Light Control and Multi-State Value Object - Room Light Control.