Questions Owners Have About Commissioning
May 11, 2021
Written by: David Chesley, PE - Director of Electrical Engineering
 
Why am I being offered electrical commissioning? I already have an electrical engineer as part of the design team, so aren’t I covered? Isn’t electrical acceptance testing the same thing? What do I get with electrical commissioning that I don’t already have with construction administration services?
 
These are some are the more common questions I’ve heard from facility managers when discussing why commissioning should encompass more than just mechanical systems. Commissioning helps to ensure that installed electrical equipment, lighting controls, and low voltage systems operate as intended. It can cover a building project’s full timeline, from ensuring that key owner goals are translated into the design from concept stages, to ensuring maintenance staff are properly trained and lighting controls and electrical systems are programmed to meet the evolving use of the building - even one year after initial occupancy. In this article, we give a high-level look of how electrical commissioning gives the owner the most value for their investment, including reducing ongoing maintenance.
 
Electrical Acceptance Testing and Electrical Commissioning: What’s the Difference?
Image 1: Commissioning encompasses project delivery from planning through operation phases, tracking initial project goals while adapting with the evolving demands on the new facility.
 
Most mission critical facilities, including many healthcare facilities, often already have acceptance testing built into the project specifications. Such testing helps to ensure that equipment was installed in compliance with project specifications and manufacturer’s installation instructions. It also ensures that equipment is initially programmed as described in owner/engineer approved shop drawings. The owner can then start the systems with both factory and field-approved testing being completed and a written record of how the system was programmed.
 
However, the process of a project being successful encompasses the full timeline from initial planning stages to troubleshooting during the operations phase.
 
Standards, such as fundamental and enhanced commissioning as detailed by both LEED BD+C version 4.0, ASHRAE Guidelines 0 and 1.1, and ANSI/NETA ECS Electrical Commissioning Specifications, have evolved to explain the benefits and process of creating a basis of design (BOD) document and owner’s program requirements (OPR). These standards incorporate testing, training, and post-occupancy follow-up requirements into bid documents.
 
From these standards, a third-party commissioning agent allows the owner to address the following scenarios that fall outside of acceptance testing:
 
  • In the planning stage, the owner agrees to the refurbishing of existing generators to save construction cost, but details are lost during design on how load shed will prioritize loads to ensure the building addition will work with the existing central utility plant.
  • During design, the owner agrees to using a wireless lighting control system with sensors integrated into the standard light fixtures to save cost, but misses that a substitution (allowed in the design) requires batteries in every light switch and not just the few discrete ceiling occupancy sensors.
  • During early construction, a review of the paralleling switchgear sequence of operation with the owner, contractor and engineer, was fine tuned so that monthly exercising not only exercised each generator for one hour per month under load, but also paralleled generators together to share load to show the synchronization is working properly.
  • A basic sequence of operation on the drawings approved by the owner allows for manual on/auto-off lighting controls in offices. By including required follow-up programming one year after occupancy, the commissioning agent was able to address end user requests to have lighting dim down to 25% instead of turning off completely, which was an option with the owner-approved lighting control system.
  • Thermal imaging performed six months after substantial completion showed that some mechanical lugs in panelboards and transfer switches, once exposed to cycling loads, were loosening enough to create hot spots. These lugs were re-tightened to meet factory recommendation on scheduled maintenance, averting a possible fault or failure while in use.
Image 2: Thermal imaging post-occupancy can be critical in catching hot spots due to loosening wire connections before they become bigger problems.
 
 
Leveraging Your Investment in New Technology
 
As recent as ten years ago (practically speaking), most lighting in workplaces were controlled strictly on/off. Backup power was limited to a central utility plant of generators. Utility metering was limited to what the utility provided you in your monthly statements.
 
Now, new technology provides the owner with new options to consider including:
 
  • Sub-metering to monitor loads by type (HVAC, lighting, EV chargers), even down to the branch circuit level in labs and data centers.
  • More sophisticated building dashboards that allow owners to see if lights remain on while a room is unoccupied and show historic energy generation for rooftop solar against weather data.
  • Lighting controls that can dim down lighting as well as shift color temperature in relation to available daylight.
  • Lithium-ion batteries and flywheels that allow owners to have longer energy storage system lifespans that can operate in broader temperatures ranges, and take up less physical space.
Electrical commissioning allows the owner to better understand their options with these new technologies, program them to serve their specific needs, and receive the training they need to maintain and upgrade them in the future with least amount of necessary labor and cost.
 
If you have further questions regarding how electrical commissioning may benefit your facility, please do not hesitate to email Scott McCullough, Allan Fox or David Chesley at Osborn Engineering for more information.
 
 
Image 3: LED lighting has brought more options for visual comfort into workplaces, including adapting color temperature of indoor lighting to match available levels of daylight.