For this project, our client was a large hospital complex in Southern Maine with an extensive low voltage distribution system with hundreds of breakers panelboards, and cables, several dozen step-down transformers, and multiple backup generators.

In order to maintain compliance with NFPA 70E, the client contracted RLC to provide a new arc flash risk assessment for the entire facility.

The RLC study also included a review of coordination of all protective devices, and identified potential changes in protection based on downstream equipment changes.
An impedance model was built in SKM including all protection and backup generation details. Scenarios were created for high and low fault current values to determine the worst-case incident energy at each bus, and additional scenarios were run with backup generation powering the facility.

Scope of Services

• Created impedance model based on gathered facility data including conductor and transformer sizes, breaker settings and fuse sizes, generator details.
• Provided a draft arc flash hazard assessment report detailing all model assumptions, arc flash scenario details, label methodology, TCCs of all coordinating protective devices, and worst-case incident energy results for client review.
• Incorporated client comments into final report with arc flash labels generated and ready for printing.