This guide suggests surge arrester installation methods at distribution cable terminal poles in order to minimize the total impressed transient voltage on medium-voltage distribution cables (up to 46 kV). Grounding electrode techniques, pole ground values, and system ground grid values are not addressed or considered in this document.
The purpose of the guide is to recommend suitable installation techniques to improve overvoltage protection schemes and thereby help ensure long term reliability. Historical surge arrester installation techniques for cable system protection may not have provided required margins of protection. Variables include the terminal-pole arrester characteristics, connection lead length, inductive voltage drop and cable system open-point and mid-point arrester utilization. Different protection schemes are presented to assist the user who is designing overvoltage protection for cable systems to estimate available margins of protection.
Revision Standard – Active – Draft.
The purpose of the guide is to recommend suitable installation techniques to improve overvoltage protection schemes and thereby help ensure long term reliability. Historical surge arrester installation techniques for cable system protection may not have provided required margins of protection. Variables include the terminal-pole arrester characteristics, connection lead length, inductive voltage drop and cable system open-point and mid-point arrester utilization. Different protection schemes are presented to assist the user who is designing overvoltage protection for cable systems to estimate available margins of protection.
Revision Standard – Active – Draft.
