Projects
A project is created for a site where Interact ready luminaires and devices are being installed. Within each project, one or more wireless networks are created based on the physical layout of the site and the number of Interact ready luminaires and devices installed. Additional networks may be required to overcome wireless obstructions on site.
Wireless Networks
Wireless networks are required to enable secure and scalable wireless communication within the lighting system and are created using the Interact Pro app or web portal.
Interact ready luminaires and devices use the Bluetooth Low Energy (BLE) wireless communication protocol to communicate with mobile phones. This enables mobile phones using the Interact Pro app to discover and add Interact ready luminaires and devices to wireless networks. In networks without gateways, BLE also enables mobile phones to deploy behavior configurations and control the lighting system locally.
Interact ready luminaires and devices within a wireless network communicate with each other using the Zigbee wireless communication protocol. Zigbee forms a wireless mesh between devices added to the network and enables the configured operation of the lighting system. The advantage of a mesh network is the capability for self-healing by using automatic route discovery.
Routing between wireless devices
The lights of a wireless system are guaranteed to work if the distance between the light and at least one of the other lights in the network is less than or equal to 10 m (depending on the sensor type). It is preferred to have at least two lights within the range of each light, as the wireless Zigbee network uses mesh routing, as shown below:
This makes the network much more robust as multiple routing paths can be used for communication.
The connection from light A to the gateway G can go via light B. If for some reason the connection between A and B is blocked, the network will automatically route the traffic through light point C.
These require the light to be installed within the reach of at least two other lights within 10 m (33 ft).
As the Zigbee Green Power devices (sensors and switches) only send messages in the Zigbee network, they exist in the network but play no role in the routing between the wireless devices.
Wireless networks operate in the 2.4GHz frequency band, which is used by 2.4 GHz Wi-Fi, Bluetooth and Zigbee. Although these technologies have been designed to co-exist in the 2.4 GHz band, it is still important to choose wireless network Zigbee channels carefully to avoid any potential interference. The Zigbee channel is user-selectable when creating a wireless network.
Channel selection
As Wi-Fi channels overlap each other, it is required to select non-overlapping channels to ensure best possible communication.
Interference between overlapping channels results in lower transmission speeds or at worst no communication at all.
In a well-managed Wi-Fi system, channels 1, 6 and 11 are used to create a network with full coverage without access points interfering with each other. Using these channels also leaves gaps in the frequency band.
The wireless Zigbee network uses channels 11, 15, 20 and 25 that are positioned in the gaps of the Wi-Fi band, as shown below:
Interference
Devices using Ultra High Frequency (UHF) radio signals are sensitive to interference. However, systems using frequencies in the 2.4 GHz band are designed to coexist.
Also, for the wireless Zigbee network, the transmitting powers are significantly lower when compared to Wi-Fi, mobile telephony etc. The table shows the relation between the maximum permitted powers for several types of radio signals.
To ensure reliable Zigbee communication within wireless networks, the following application-specific distance limitations between luminaires and devices should be observed:
Office/Educational Institution applications - 10 m (33 ft) Industry/Warehouse/Retail applications - 15 m (49 ft) Outdoor Parking applications (only for LCN4120, LCN4150) - 49 m (160 ft)
Distances vary depending on the sensor type, refer to each sensor data sheet for maximum distances allowed by each device.
Wireless gateways should be within the specified application range of at least two mains powered wireless luminaires or devices in their respective wireless networks. Ideally, they should be mounted in a central location within the network for maximum reliability. Zigbee Green Power (ZGP) devices do not count as devices in range in this instance since they do not repeat Zigbee messages.
Groups
Groups are created within wireless networks using the Interact Pro app or web portal. Groups are where the behavior of the smart lighting system is defined. Groups enable Interact ready luminaires and devices to be linked together wirelessly to respond to occupancy, vacancy and light level using various configurable light behavior templates. They also enable user interface control, scene setting and schedule control.