Monitoring the quality of T&D construction through statistical sampling techniques

The Commonwealth Edison Company (CECo) of Chicago has developed a methodology for auditing distribution systems based on statistical principles. The foundation and structure of the methodology reflects the vision and philosophy of the company. The methodology is applicable to all overhead distribution systems. Overhead distribution may consist of new poles installed as well as existing pole upgrades. This paper shows how to monitor the quality of distribution construction, through the use of statistical qualify audits. The procedure demonstrates that quality audits identify areas of both compliance and noncompliance to company standards, they provide the user with the necessary instrument of measuring conformance to standards, and they establish a platform for identifying and correcting any standards and specifications that require improvement. It is an important tool in the achievement of quality. The methodology is based on the research and recommendations proposed by CECo Task Force Committee for Conducting Operating Audits and have been validated with actual system measurements