This article provides answers to commonly raised questions about Area Occupancy.
Questions:
Q: What is the general zone sensor behavior?
- Area occupancy is registered immediately when a person walks into the room. If occupancy is not detected after 90 seconds, the area will be registered as Not Occupied.
- An area can have a single sensor, a group of sensors in a room, or all sensors on a floor. Note that an area cannot exist between floors.
- When there are multiple sensors in an area, and if any sensor detects occupancy, the area will be registered as “occupied.” For example, if four sensors exist in an area, and if one sensor detects occupancy, it will immediately send the information to the Energy Manager, and the area will be registered as “occupied” for that area API point.
- Wireless Network Strength and Reliability: When a sensor cannot send a signal to the gateway due to wireless network interference or gateway network outage, then the last state of the area will be upheld. This last occupancy state will be maintained until an additional occupancy event is triggered or a 5-minute pm stat update occurs. For example,
- When an employee walks into a conference room and is perfectly still, the occupancy information has not reached the Energy Manager due to network strength and low reliability; the area may not be registered as “occupied.”
- If a person walks into the room and triggers an occupancy event, and if the network is down, the sensors will be unable to communicate to the Energy Manager. The room will stay in the “occupied” state for longer than 90 seconds.
- The recommended pull time for using the Zonal Occupancy API by a third party is 1 minute. Note that a shorter time will increase the load on the system. If the pull time is longer than 90 seconds, then you could probably miss an occupancy window.
Q: Does real-time area occupancy status via BACnet require area occupancy API subscription and IoT sensor licenses?
A: No. Only Connected Lighting sensors are required for BACnet functionality. Customers only need to purchase the appropriate number of BACnet group (and base) point licenses (see BACnet licenses).
Q: A BACnet client requesting Area Occupancy status via BACnet might not see the correct zonal occupancy/vacancy status for 5-15 minutes because the BACnet server application only polls the Manage database at a 5-minute interval. Is that right?
A: Yes. The BACnet server application polls the Manage database at a five-minute interval.
Q: Will a RestAPI call to Manage provide the most recent area (zonal) occupancy status in the Manage database?
A: Yes. When an area is enabled as a zone sensor and API License (EM-API-OCC) has been purchased based on the number of sensors configured in the system, you can expect sub-minute end-to-end latency.
Note: The RestAPI call is serviced by a different Manage software task than the Manage’s BACnet server task.
Q: If Zone Sensor is enabled, will a zoned sensor report an occupancy event immediately to Manage, and will it report a vacancy event 90 seconds after the most recent occupancy detection?
A: Yes. The sensor sends the Area Occupancy Status to Manage by Real-Time packet when the Area Occupancy Status: occupied (1) or unoccupied (0) event occurs. When the event occurs, a counter of 90 seconds starts on the sensor, not Manage. An API license is required to enable a Real-time packet.
Note: The sensor can also send occupancy status to Manage by PM stats packet every five minutes by default.
Q: When areas are enabled as Zone sensors for use by BACnet, why does the Manage license page display an out-of-compliance warning message?
A: A bug in the license enforcement feature creates an out-of-compliance warning message when areas are enabled as zone sensors for use by BACnet. This warning message can be ignored and will not adversely affect system operation. This defect will be addressed in a future version.
Workaround for out-of-compliance warning message:
Customers, please get in touch with Enlighted Support.
Support team, please follow these steps:
- If the customer has IoT sensors, grant the customer the appropriate number of one-year real-time area occupancy API licenses to bring the system back into compliance and remove the warning message.
- If the customer has Connected Lighting sensors, the warning message will not negatively impact the system in any way.
Please review the release notes of future releases and upgrade the system when new versions become available.
Q: Does placing a sensor into an Area and enabling Zonal Occupancy immediately start reporting occupancy events in addition to PM stats?
A: Yes. The sensor reports area occupancy status in addition to the PM stats. Refer to Enable Zone Sensors to enable sensors in an area to report occupancy.
Q: If a sensor is placed in an area without enabling Zonal Occupancy, will it still report Occupancy status?
A: No, the sensor will not report Occupancy status if Zonal Occupancy is not enabled.
Q: Does such a sensor only report the first occupancy event in the vacancy state, or does it report each time it detects motion?
A: The sensor will report Occupancy Status via Real-Time packet every 90 seconds as long as it continuously detects motion.
Q: Is the 90-second vacancy timeout implemented (counted down) in the sensor or Manage? Does the sensor send a message to Manage reporting a state change to a vacancy?
A: The 90-second timeout is set on the sensor. The sensor then sends the message to Manage to change the state to vacant. This parameter is non-configurable.
Q: How does the 90-second timeout value correlate with the Active Motion Window (AMW) value in the sensor's profile?
A: There is no relationship between the 90-second timeout and AMW. AMW is how long the light will be on after the sensor has not detected motion. If the sensor detects continuous motion, it will tell Manage in real time that occupancy is true. The AMW timeframe (not value) will increase every 90 seconds.
Q: When 600 zonal areas exist in Manage, can all zones send data to BMS via BACnet, and about 100 zones send data to the third-party systems via APIs? Will this work, or should the number of zones be the same for both API and BACnet?
A: This setup will work. The customer can have the same zones to send data via BACnet or APIs to multiple third-party systems.