IEEE C57.104-2008 pdf free.IEEE Guide for the Interpretation of Gases Generated in Oil-Immersed Transformers.
Many techniques for the detection and the measurement of gases have been established. However, it must be recognized that analysis of these gases and interpretation of their significance is. at this time, not a science but an art subject to variability. Their presence and quantity are dependent on equipment variables such as type, location, and temperature of the fault: soluhility and degree of saturation of various gases in oil; the type of oil preservation system; the type and rate of oil circulation: the kinds of material in contact with the fault: and finally, variables associated with thc sampling and measuring procedures themselves. Because of the variability of acceptable gas limits and the significance of various gases and generation rates, a consensus is difficult to obtain. The principal obstacle in the development of fault interpretation as an exact science is the lack of positive correlation of the fault-identifying gases with faults found in actual transformers.
The result of various ASTM testing round-robins indicates that the analytical procedures for gas analysis are dillicult. have poor precision. and can be wildly inaccurate, especially between laboratories. A replicate analysis confirming a diagnosis should bc made before taking any major action.
This guide is intended to provide guidance on specific methods and procedures that may assist the transformer operator in deciding on the status and continued operation of a transformer that exhibits combustible gas formation. However, operators must be cautioned that, although the physical reasons for gas formation have a firm technical basis, interpretation of that data in terms of the specific cause or causes is not an exact science. but it is the result of empirical evidence from which rules for interpretation have been derived. Hence, exact causes or conditions within transformers may not be inferred from the various procedures. The continued application of the rules and limits in this guide, accompanied by actual confirmation of the causes of gas formation, will result in continued refinement and improvement in the correlation of the rules and limits for interpretation.
Individual experience with this guide will assist the operators in determining the best procedure. or combination of procedures. for each specific case. Some of the factors involved in the decision of the operator arc: the type of oil preservation system, the type and frequency of the sampling program, and the analytical facilities available. However, whether used separately or as complements to one another, the procedures disclosed in this guide all provide the operator with useful information concerning the serviceability of the equipment.
2. Normative references
The following referenced documents are indispensable for the application of this document (i.e., they must be understood and used, so each referenced document is cited in text and its relationship to this document is explained). For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments or corrigenda) applies.IEEE C57.104 pdf free download.