IEEE 1346

Description / Abstract: This recommended practice is intended to be applied at the planning or design stage of a system where power supply and equipment choices are still ßexible and incompatibilities can be resolved. The cost of trying to Þx an incompatible system after installation is hundreds to thousands of times more than addressing it in the planning stage. Consequently, this document does not discuss troubleshooting or correcting existing power quality problems.

Since voltage sags present the greatest Þnancial loss due to compatibility, this Þrst edition of the recommended practice develops a compatibility methodology speciÞcally for voltage sags. However, compatibility encompasses many other issues such as harmonics, surges, radiated interference, etc. As better information is available on the environment/equipment response and experience is gained with this approach, compatibility methodologies will be developed for other issues. To aid the evaluation of the non-sag compatibility issues, a guideline list is included in 4.3.

This recommended practice does not discuss technical options to improve compatibility. The alternatives are so numerous and evolving so quickly that such a listing would detract from the basic purpose of the document, which is to plan for compatibility.

Clause 4 is the heart of the document and contains the worksheets used for evaluating compatibility. Completed worksheets provide an estimate of the number of disruptions, the Þnancial loss, and Þnancial analysis of alternatives associated with the compatibility of a system. The annexes provide the background and techniques necessary to apply the worksheets. They are Þnancial analyses, power system performance, equipment performance, and constructing the compatibility charts. An example analysis is provided in Annex E.