This standard applies to "series connected" dry-type air-core single-phase or three-phase outdoor or indoor reactors of distribution and transmission voltage class that are connected in the power system to control power flow under steady state conditions and/or limit fault current under short-circuit conditions. Dry-type air-core reactors covered by this standard are self-cooled by natural air convection. With some restrictions, this standard is applicable to filter reactors, shunt capacitor reactors (used with shunt capacitor banks), and discharge current-limiting reactors (used with series capacitor banks). Annexes A, B, and C are included to provide guidance.This standard does not apply to devices such as a) Shunt reactors (see IEEE Std C57.21-1990, IEEE Standard Requirements, Terminology, and Test Code for Shunt Reactors Rated Over 500 kVA), b) Arc suppression coils, c) Neutral grounding devices [see IEEE Std 32-1972 (Reaff 1990), IEEE Standard Requirements, Terminology, and Test Procedures for Neutral Grounding Devices], d) Line resonant reactors, e) High-Voltage direct current (HVDC) smoothing reactors, f) Forced cooled reactors, and g) Line traps and radio interference (RI) filter reactors (ANSI C93.3-1995).