Overview

In accordance with the standard of care required for electrical design and the requirements of the National Electrical Code (NEC) and NFPA 70E, Standard for Electrical Safety in the Workplace, due diligence investigations including a Short Circuit and Device Evaluation Study, a Coordination Study, and an Arc Flash Study significantly contribute to safe and reliable electrical system operation.

To document the existing configuration for a portion of the 10-MGD Eastvale Water Treatment Plant (WTP) electrical system and to quantify the arc flash risk at each critical location within that system, BFMA engaged Entech to provide these three recommended correlating studies. Our comprehensive Power System Study modeled the electrical system from the incoming service to the secondary panels and control panels and provided a subsequent report documenting the analyses, arc flash results, and any recommendations to reduce arc flash risk levels, replace overdutied equipment, and/or improve protective device coordination.

A major portion of the electrical system at the Eastvale WTP is supplied by the High Service Pump House’s 480 V, 3-phase electrical service. This service, which also draws auxiliary power from a 750 kW diesel generator via an automatic transfer switch, supplies all electrical power to the Pump House itself and distributes power to several other buildings at the WTP, supporting a total of 52 distribution panels, circuit breakers, switches, and control panels spread across six buildings.

To provide BFMA with a comprehensive Power System Study of the Pump House electrical service and all associated downstream electrical distribution equipment, Entech first completed a short circuit analysis and equipment duty evaluation to calculate available fault currents and identify overdutied equipment. We then completed a protective device coordination study to identify any areas in need of adjustment to ensure proper fault isolation. Finally, using the results of these two studies, we performed an arc flash hazard analysis to calculate expected arc flash incident energy levels and boundaries at each potential location of energized work. We made recommendations for any adjustments necessary to maintain an optimum balance between arc flash hazard reduction and protective device coordination and to improve the overall safety and reliability of the facility’s electrical distribution system.

Our final report prioritized and summarized these recommendations so that BFMA has a clear path as they move forward with capital improvement and ongoing maintenance projects.

As part of our service to BFMA, we also provided labels that they can affix to each piece of major electrical equipment (switchgear, panelboards, motor control panels, motor disconnects, etc.), indicating the arc flash hazard information calculated for each respective component.

Our comprehensive Power System Study services are supporting BFMA in maintaining safety and efficiency in their electrical systems operations as part of a comprehensive electrical safety program.