Industry standards such as ANSI/TIA-568 and ISO/IEC 11801 provide the following guidelines: Unshielded Power Cables:50 mm (2 inches) for up to 2 kVA power cables. IEEE Standards documents are developed within the IEEE Societies and the Standards Coordinating Committees of the IEEE Standards Association (IEEE-SA) Standards Board. The IEEE develops its standards through a consensus development process, approved by the American National Standards Institute. Abstract: The design, installation, and protection of wire and cable systems in substations are covered in this guide, with the objective of minimizing cable failures and their consequences. Printed in the United States of America. 3 named (Low Voltage Planning Criteria) in the existing SEC Distribution Planning Standards (DPS, Rev.