Stationary battery systems are among the most critical substation assets and are often the most overlooked. Recent changes to the North American Electric Reliability Corporation’s (NERC’s) Protection System Maintenance requirements, PRC-005-2 in particular, have placed new importance on these critical systems by including strict inspection, testing and maintenance requirements for bulk electric system (BES) battery systems. This document makes clear distinction between direct-current (DC) supply components that are continuously monitored and those that are not. Additionally, flooded lead-acid (FLA), valve-regulated lead-acid (VRLA) and nickel-cadmium (NiCd) batteries have different inspection, testing and maintenance requirements.

To comply with NERC’s requirements, utilities will need to make changes to maintenance practices that, likely, have been in place for many years. Battery monitoring systems enable the attention required for this asset, while greatly reducing resources that would otherwise be required, and can provide the necessary documentation to support NERC’s requirements.

Deserved Attention

Battery monitoring systems enable maintenance personnel to better determine the operating condition of DC supply systems, which are critical to the safe and reliable operation of the electric system. NERC and other regulatory agencies have placed strict operating and maintenance regulations on many critical electric system components, including battery systems. Failure to comply with these regulations could result in harsh monetary penalties. Battery systems have lived in the shadow of high-tech components such as protective relaying and,
often, have been overlooked as critical components. In reality, devices protecting the electric system cannot operate safely and reliably without a properly maintained and operational DC system.

Additionally, with reduced maintenance budgets, the loss of specialist crafts personnel and the reduction in maintenance staffing, regulatory compliance may be compromised without accurate data gathering, analysis and storage capabilities. Battery monitoring systems also enable users to obtain real-time information and act in a timely manner, should an issue arise.