Connected Lighting Systems: Control
The topics we have discussed so far (tunable white lighting and POE) enable many of the advantages of a CLS (Connected Lighting System), but one of the bigger features of a CLS is the control system. A luminaire can only bring so much to the table on its own without some sort of a decision-making mechanism. A control system is what makes analyzing information from a variety of input sources to adjust lighting, pushing information to alarm systems, and making security decisions for a facility possible.
Control systems are at the heart of Hubbell’s business. In fact, back in 1896 our founder Harvey Hubbell patented the world’s first lighting control device, the pull-chain lamp socket: a mechanism for turning a light bulb on and off. A simple start, and the first step in a path that has created many powerful control systems for commercial buildings today.
Hubbell offers two styles of control systems to meet the varied needs of their customers, and each provides unique features. The first is a centralized control system, where each component is monitored or controlled via one decision-making processor, usually located in the electrical closet.
The CX control panel from Hubbell Control Solutions is based on this model. Switches or sensors, either motion sensing or daylight harvesting, provide information to the control panel. The panel then makes decisions based on this input and system programming and turns luminaires on and off or adjusts brightness and color temperature based on the information it receives. Changes to the lighting can also be scheduled based on time of day and day of the week. Programming is centralized to the CX control panel.
The City of Greenville Public Works Department utilizes a CX control system in their new public works department campus to provide convenient on/off control while also enabling programmed control of areas that need to have lighting levels set for security purposes. You can read about their utilization of the CX control system here.
The second option for control is a distributed control system, where individual components contain decision-making capabilities and communicate with other devices directly. In this situation, there is no need for a central control unit. Our NX Distributed Intelligence™ control system is an example of just such a distributed control environment that utilizes a Distributed Network Architecture (DNA) connecting intelligent devices including luminaires, controllers, panels, occupancy sensors, photocells, wall switches, and dimmers, to create a system that is simple, scalable, and versatile. Programming at the device level allows the devices to change the lighting according to a schedule or monitor other devices such as sensors and switches on the network and decide for themselves what actions they need to take. All of this comes without the need for operational dependencies on software, gateways or servers.
For smaller installations of the NX system, programming takes place per device, and can be handled by a smart phone app using Bluetooth® wireless. In larger installations, a large number of devices can be programmed using a web browser based interface through an Area Controller, that can also be connected to a BMS (Building Management System) using BACnet™ to monitor and control the lighting. A luminaire can be instructed to directly monitor a daylight sensor, switch, or occupancy sensor and respond to changes in those devices without the need for a higher-level controller.
Both are effective control options, with the NX system able to scale up to significantly larger installations over what the CX panel can handle. Additionally, when connected to a BMS the sensor data available through a Hubbell NX CLS system can be shared with other building services such as security and HVAC control systems without the need for a gateway device to attempt to translate from a proprietary control communications protocol to BACnet™. Direct support of BACnet™ means you get a more reliable and stable control system for your facility.
Lexington Medical Center in South Carolina utilizes the NX control solution in a recent expansion project to ensure that nursing staff can easily adjust lighting in patients’ rooms and other spaces for optimal conditions for the task to be performed, and yet maintain appropriate minimum lighting levels for the safety of staff and patients alike. Click HERE to read about this important healthcare project.
Next, we’ll discuss the details of the architecture needed to support a control system.