Case study: Office space upgrades wireless lighting controls
An MEP firm’s experience upgrading its own office with wireless lighting controls provided insight into the potential benefits and pitfalls of the technology.
For Peter Basso Associates’ recent office refresh, the project team grappled with many of these very issues. The result combines energy-conscious control parameters as well as aesthetically pleasing spaces. The office went from 1990s-era T-8 fluorescent continuous direct-indirect pendants using 1.1 watts per square foot to LED pendants using just 0.34 watts per square foot.
The change of lighting source accounted for most of the energy savings, and upgrading to a wireless control system allowed for increased user control, greater use of dimming and vacancy sensors and daylight harvesting around the building perimeter along with observable real-time energy monitoring. Going through this process firsthand gave the project team an up-close experience in design, specification and installation of a wireless control system, as well as many lessons learned, which will further benefit clients.
The team worked closely with both the local manufacturer’s representative of the controls company and the installing contractor and despite the level of expertise and the additional coordination, there were some hiccups along the way.
For example, the equipment submittal wasn’t as detailed as preferred. As the end users of the space, the team knew the level of functionality that was required, however, the team was relatively inexperienced and unfamiliar with the wireless system that was selected and its individual parts and pieces of the system and compatibility between those parts and pieces.
Example: “You want the conference rooms to have local control but also to have the ability to not be affected by office wide sweeps? Well then we need to make sure there is a Cat 5 connection back to the server.” This is where a riser diagram and device layout are indispensable, because not all components of the wireless control system are themselves wireless and an installing contractor needs to know that for bidding and, more importantly, installation.
In another instance the installing contractor did not provide low-voltage connections among a group of fixtures, which remained undiscovered until the commissioning technician was on site to configure the system. This was a pretty easy fix as it was only a handful of fixtures in an area with 9-foot tile ceilings. Had it been a higher or a drywall ceiling with more fixtures, it very well could have required a much more expensive fix. After the fact, the company’s IT administrator poked his head above the ceiling to troubleshoot the enigma brought on by the office refresh and wondered where all the new Cat 5 cabling was coming from and going to.
Early in the planning and design process, the design team discussed with the IT administrator where the brains of the system would live and whether there would be any connections between the network and the lighting control system. Initially it was decided that they would be separated, however, to take advantage of a lighting controls rebate offered by the utility company, the team needed to have the two connected for trend monitoring, reporting and backup. While the office is not located in an area where load shedding or demand response are widespread, to participate in utility rebate programs, an outside connection to the utility was needed, which also opens up a lighting control system and — by extension — a company’s network to unwelcome intrusion, making security critical.
Peter Basso Associates’ experience was fairly uneventful with no major problems; however, the experience increased the staff’s ability to provide better guidance to clients and to further understand the critical questions to ask of manufacturers.
For example, it’s important to obtain control device cutsheets from a manufacturer as well as a control riser diagram that identifies where devices are located as well as the wiring types they require. We now even ask for a cable legend to show what is low voltage, Cat 5 or wireless. As stated previously, no system is truly wireless, therefore having a legend that calls out the wiring specification requirements can help a contractor provide an accurate bid for installing lighting controls.
It also is recommended that the design team ask the manufacturer to provide any limitations to the control system that they should be aware of and if there are limitations, work with the team on solutions to bypass them. Providing the manufacturer with a written narrative of expectations of the system being used and what will be required of it can eliminate ambiguity and allow all parties involved to work toward meeting those expectations. Simply put, a device layout and a binder of cutsheets will not convey how a system will work, what it will look like or the functionality it will have, which is ultimately what the end user of a space really cares about.
It is not uncommon to compare wireless lighting control systems from various manufacturers, to try to find the best fit for the client, budget or space-use function. Thorough documentation adds to the ease of identifying differentiating features and options for comparison purposes. It also is beneficial for evaluating a protocol or manufacturer’s capability, of integrating additional lighting layers that aren’t considered part of the architectural system (downlights, troffers, etc.). The coordination of a chandelier or series of decorative pendants, for example, without on-board wireless lighting control capabilities adds time and complexity to a project — and expectation management.
Open protocol controls are easier to use, the term “wireless” representing a number of protocols such as Zigbee, Bluetooth, Wi-Fi (frequency dependent), etc. A single manufacturer providing all the lighting and the wireless lighting control is the best-case scenario in terms of troubleshooting, commissioning, etc., but it’s rarely how a project goes.