It is a common misperception that electrical commissioning and acceptance testing are the same thing or that electrical commissioning is the same as equipment startup.  In reality, acceptance testing and equipment startup are only two subsets of the electrical commissioning process.  Upon completion of acceptance testing and contractor/vendor startup (pre-functional testing), functional performance testing (FPT) and integrated systems testing (IST) is executed (Figure 1).

What Is Electrical Commissioning?

In the ANSI/International Electrical Testing Association — Standard for Electrical Commissioning Specifications for Electrical Power Equipment and Systems (NETA ECS-2015), electrical commissioning is defined as the systematic process of verifying, documenting, and placing into service newly installed or retrofitted electrical power equipment and systems.  The process focuses on verifying and documenting that all of the electrical commissioned equipment, systems, and assemblies are planned, designed, installed, tested, operated, and maintained to meet the owner's project requirements (OPRs) per ASHRAE Standard 202-2013  — Commissioning Process for Buildings and Systems.

Commissioning is critical for all new or retrofit installation projects to verify the correct system operation to the design intent, which ensures safe, reliable operation of the electrical system.

The commissioning process involves OPRs,  a basis of design (BOD), factory acceptance tests, field acceptance tests, verification of the component interconnections, and functional testing of the system in part and in whole (IST). Acceptance testing and commissioning work (FPT) provides baseline results for future routine maintenance of the system and related components.

Acceptance testing is performed to confirm equipment is built, installed, and calibrated to functions per the design specifications. Field tests assesses the suitability of the initial energization of electrical power equipment and systems, ensures performance expectations are met, minimizes downtime, and maximizes the life expectancy of equipment.

When to Initiate Electrical Commissioning

To be most effective and realize all of the benefits of electrical commissioning, the electrical commissioning provider should be engaged from the pre-design/programming phase throughout the design, construction, acceptance testing, occupancy, and post-occupancy phases.  This allows problems to be found as early in the process as possible, reducing the cost and rework as necessary. The electrical commissioning process progresses along with the building commissioning process to ensure all aspects of the electrical system are tested and verified.

The Commissioning Team

The commissioning team is usually made up of the owner/owner’s representative, a building commissioning provider, an electrical commissioning provider, the architect or engineering representative, general contractor, subcontractors, other vendors, and operations and maintenance  staff.

The owner/rep provides the commissioning provider with all electrical plans and supporting documents that will be used to validate the equipment and system design against the power and operational requirements of the facility. Specific deliverables include, but are not limited to engineering studies, electronic setting files, electrical drawings and specifications, factory and field acceptance reports, project schedule, site-specific hazard notification and safety training, OPRs, BOD, designated representatives for the project commissioning activities.

The electrical commissioning provider acts as a trusted partner and consultant. According to ANSI/NETA ECS-2015, it is recommended that the commissioning organization be an independent, third-party entity that can function as an unbiased authority, professionally independent of the manufacturers, suppliers, and installers of equipment or systems being evaluated. The organization and field personnel should be regularly engaged in the commissioning of electrical equipment, devices, installations, and systems and submit appropriate documentation to demonstrate that it satisfactorily complies with these requirements.

The specific duties of the commissioning provider include the oversight, execution, management, and organization of the entire electrical commissioning process. The commissioning organization will provide the following:

  • All necessary services and technical expertise to conduct electrical commissioning.
  • Notification to the designated representative(s) prior to the commencement of any electrical commissioning activity.
  • Timely notification of deficiencies based on the results of the commissioning activities.
  • Written record of all electrical commissioning activities and a final report.

Electrical Commissioning and the Big Picture

Commissioning and acceptance testing have been key disciplines in building processes for many years. Only recently has there been a more specific focus on electrical commissioning. The increasing complexity of electrical systems and the growing intolerance for unplanned downtime prompted the development of the ANSI/NETA ECS to expand the building commissioning scope and further enhance system evaluation more thoroughly than acceptance testing alone.  Proper electrical commissioning can identify potential issues in design, equipment specifications, installation, functionality, performance, and environment that could result in failures or outages down the line. It is estimated that roughly 70% of early power system failures have been linked to design, installation, or startup deficiencies.  By requiring an electrical commissioning provider as part of the commissioning team, owners and contractors can ensure safer installations, fewer construction delays, more efficient startups, and a more reliable power supply once energized. An independent commissioning provider will confirm the electrical equipment and systems have been installed properly to minimize any future downtime and maximize the life expectancy of the equipment and systems.