MH Controls Corner: Defining “Networked Lighting Controls”

"The beginning of wisdom is to call things by their proper name.” – Confucius

The term “Networked Lighting Controls” has been popping up a lot more recently on engineers’ lighting plans and specifications. And rightfully so, today’s energy codes often require controls devices that use Ethernet cables and wireless communications to meet code and design intent. So, what truly makes a lighting control system networked? Let’s run through some of our controls basics to try and determine when it is appropriate to refer to a system as being networked vs. standalone in today’s controls lingo.

To provide a little bit of background on this topic, we will define a standalone system as a single device or group of components controlling the lighting within a single space of the building, be it an office, a classroom, or a cafeteria. The devices, room controllers, sensors, and switches within that room might have the ability to communicate to one another in order to meet the required controls intent, but that is where the communication stops, isolated to that one space, and therefore it is considered to be standalone. Networked controls are a bit more expansive; they allow the communication of the control devices in a single room to communicate beyond the walls of that room via network backbone, wired or wireless. Networked controls open the door to a lot more possibilities that we will touch on below.

Back before the 2012 IECC, networked lighting controls systems were few and far between, existing on maybe a handful of projects that had special requirements, such as platinum LEED certification. Most automated control requirements were capable of being met with a standalone, line voltage occupancy sensor; it was truly standalone and did not have the need to tie into anything other than the lighting circuit it was intended to control. Those were the simple days and controls were…controls.

Skip to 2015 IECC and beyond, and now we are required to meet such things as vacancy mode and daylight harvesting, and deal with multi-zone environments like classrooms and conference rooms that also may demand scene controls. All of a sudden, that standalone line voltage sensor is no longer capable of handling the job, and indeed, line voltage sensors are rarely seen on 2015 IECC projects, with the exception of maybe private offices, public restrooms, or janitor closets. We now have to use multiple devices, such as low voltage photocells, ceiling sensors, and low voltage dimmers or scene switches communicating to one another in a single space. Surely line voltage wire would not be the proper means for that communication to happen. This would require low voltage cable between these devices, and better yet, plug and play Ethernet cable, in order to ensure that none of these devices get miss-wired and damaged at installation. Now that we have a room full CAT5 cable between our controls devices, or better yet, no cables at all with the devices able to wirelessly communicate to one another, do we have a networked lighting control system? Yes and no. The devices are communicating to one another over what is often referred to as network cable, however that room is still standalone. There is no means for any network to access the control devices within that single room, so it is still, by definition, standalone. It is, however, appropriate to refer to these types of controls systems as “digital,” or in the case of wireless…”wireless.”

To make a control system truly networked, we have to add the ability to communicate to the devices in any room on a project from a central location, whether from within the facility itself, or remotely via a computer interface that has access to the building’s network. These systems are the ones we typically refer to as networked systems. They offer the ability to monitor the status of any control device on the system, and are connected to a central interface, such as a JACE or a wireless router. These systems are capable of being connected to other systems within the facility, such as BAS, security, fire alarm, or even data acquisition and monitoring systems. Networked controls systems allow the end user to keep track of which loads are on or off, and which spaces are occupied throughout their building, or in some cases, many spaces across multiple buildings. Additionally, and maybe most importantly, it would allow them to make adjustments to any networked device on their system, such as an occupancy sensor, photocell, or a load in the relay panel from a central or a remote location. Adjustments such as sensor timeout settings to accommodate space usage in order to save additional energy can be made. The ability to set specific schedules to accommodate special facility events can also be completed through a single user interface. HVAC system integrators can now also have access to the lighting controls occupancy or vacancy sensors, and be able to use sensor status to operate heating and cooling. All of these features are what make a lighting controls system truly networked.

So the next time you come across the term “networked lighting controls,” ask yourself, what are they really trying to achieve? Perhaps all they desire is a system that uses CAT5 cables to plug and play. Or, maybe they want to be able to control the lights in that one classroom from across the ocean. The variance in architecture and cost of these two options is vast, yet the term “networked” can be used for both. As always, clearly defining what the system is to accomplish is the best way to ensure that the correct system for the application ends up on the project.

Remember, whenever you have a technical controls question on any project or application, simply email controls@mhlighting.com. This email address is monitored by our entire controls team. During our normal business hours, we are committed to a four-hour response time for all emails sent to this email address!

This article was written by Mike Bogomolov, our Controls Engineering Supervisor. Mike can be reached at 720.904.8537 or mike@mhlighting.com.