IEEE C37.113-2015 is a technical guide for protective relay applications to transmission lines, focused on power-system protection practice. It addresses how relaying is applied to line protection schemes in transmission networks, helping engineers evaluate design choices, coordination, and expected performance. In utility and industrial power environments, this standard supports more consistent relay application decisions and reduces the risk of misapplication in critical transmission-line protection.

IEEE C37.113-2015 overview

This standard provides guidance for applying protective relays to transmission lines, where dependable fault detection and selective clearing are essential. IEEE C37.113-2015 is relevant to protection engineers working with components, circuits, devices, and systems in power transmission. It is typically used to inform scheme selection, relay setting philosophy, and coordination considerations for line protection. The document is especially useful when comparing protection approaches for different line lengths, system configurations, and operating conditions.

Typical use cases

IEEE C37.113-2015 is commonly referenced when designing or reviewing transmission-line protection schemes for substations, utility networks, and other high-voltage power systems. It may be used during relay specification, protection studies, commissioning checks, or retrofit planning for line relaying equipment. Engineers can use it to align protective relay application choices with the characteristics of overhead lines, interconnections, and system operating requirements, particularly where dependable isolation of line faults is a priority.

Why this standard matters

Protective relay application on transmission lines has direct consequences for safety, reliability, and system continuity. IEEE C37.113-2015 helps bring structure to technical decisions that affect fault clearing, coordination, and protection performance. Using a recognized guide can support more consistent design and procurement decisions, while also helping reduce miscoordination or unintended tripping. For organizations responsible for power transmission assets, it provides a practical reference for applying protection in a controlled and defensible way.

• Transmission-line relay application guidance
• Protection scheme selection and coordination
• Utility and power-system engineering reference
• Relay setting and review support
• Fault-clearing and reliability focus