With the advent of solid state lighting, we are now able to add intelligent controls to the lighting solutions. Already existing circuitry designed to control and dim the LEDs can easily be added on to include wireless control; a microcontroller can use its dormant Rx/Tx pins and connect to a wireless transceiver, instantly creating a wireless solution.
Wireless controls range from intelligent home automation to whole factory control. The fact that no control wires are required allows the customer to place the lighting controller wherever deemed most convenient. This means that adding a wireless switch at home would not require the costly addition of a junction box and wiring it directly to the light source. Wireless controls also allow for mobile control; from a laptop on the manufacturing floor to an iPad on your living room couch. Wireless solutions with a gateway to the internet can even be monitored and controlled from a remote location via the internet connection.
Some of the networks implemented by wireless control are mesh networks and point-to-point networks. Mesh networks occur when each light acts as an individual node, passing controlling data through the network. This allows for a larger range of communication from the initial command point as the signal gets passed from node to node until it reaches its final destination. Conversely, a point-to-point network occurs when a single remote manipulates a single light source.
There are many different solutions to wireless control in LED applications. Some of the leading communication protocols are IR (infrared), Zigbee and Wi-Fi. IR controls, while a tried-and-true communication path, has become antiquated because its range and light of sight disadvantages have been overcome by other advances in wireless communication. Zigbee and Wi-Fi, on the other hand, take advantage of radio waves to extend the range and remove the line-of-sight requirement.
Zigbee is IEEE 802.15.4 compliant and uses a mesh network and low data rates to connect many nodes to each other. Because Zigbee is a standard, it allows for interoperation with existing zigbee products that include many other controls then just lighting. Communication directly between a zigbee light source and a zigbee sensor can be achieved without the need for human control. The zigbee alliance boasts 64,000 individual nodes on a single network; however an extra gateway device is required to interface the zigbee communication to the internet. This means that a gateway is required if you want your PC or IPhone to communicate to a zigbee network.
Another popular communication protocol is Wi-Fi. While Wi-Fi is limited to only 255 nodes per access point (although it is often recommended that the number be less than 30), it can handle large amounts of data and is already connected to the internet via a router. This makes Wi-Fi a good choice for advanced lights that a consumer may only need a handful of.
When choosing a wireless solution for your lighting needs, it is important to consider the quantity of nodes per network as well as the need for internet connectivity. For example, many LED lights in a manufacturing warehouse can easily take advantage of a large mesh network solution that the zigbee affords. However, controlling a single strip of colored LEDs from your IPhone lends itself to Wi-Fi connectivity because it could connect directly to your router.
Here at Norlux we are committed to explore and understand all developments in wireless control of LED lighting. If you are interested in a wireless LED solution, please contact the engineers at Norlux.
