PwrTrans-TapChgr - Power Transformers - Tap Changers

Craig Colopy

This part of IEC 60214 applies to on-load tap-changers of both resistor and reactor types, deenergized tap-changers, and their motor-drive mechanisms. It applies mainly to tap-changers immersed in mineral insulating oil according to IEC 60296 but may also be used for tap-changers with air or gas insulation or immersed in other insulating liquids insofar as conditions are applicable. It applies mainly to tap-changers with arcing contacts but may also be used for arcing-free on-load tap-changers (such as electronic switching) insofar as conditions are applicable. This part of IEC 60214 applies to power and distribution transformers of all types and also to reactors. It does not apply to transformers and reactors mounted on railway rolling stock.

This standard covers electrical and mechanical performance and test requirements for tap changers installed in voltage regulating power and distribution transformers of all voltage and kVA ratings. It covers load tap changers (LTCs), also known as on-load tap changers (OLTCs), which can change taps while the transformer is energized and carrying load; and it covers de-energized tap changers (DETCs), also known as off-circuit tap changers, which may be operated only while the transformer is not energized. For load tap changers, this standard covers both resistor and reactor types. It also covers certain aspects of the attendant tap changer motor-drive mechanism. It does not cover the tap changer control system (manual or automatic).

This part of IEC 60214 is intended to assist in the selection of tap-changers designed in accordance with IEC 60214-1 or IEEE Std C57.131 for use in conjunction with the tapped windings of transformers or reactors. Requirements, references and definitions relevant to either IEC 60214-1 or IEEE Std C57.131 are given and their use is described in Clause 4. It is also intended to assist in understanding the various types of tap-changers and their associated equipment available. These application guidelines cover on-load tap-changers (resistor and reactor types) and de-energized tap-changers.