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). The existing ANSI C57.16-1958, which is still in use by the industry, is out of date and has been withdrawn as an IEEE standard. It has now been revised to reflect modern product technology, to describe up-to-date test methods, and to present application requirements for series reactors. New IEEE Standard - Superseded. Series-Connected dry-type air-core single-phase and 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 are covered. Dry-Type air-core reactors covered by this standard are self-cooled by natural air convection. With some restrictions, other reactors, including shunt capacitor reactors (used with shunt capacitor banks), filter reactors, shunt capacitor reactors (used with series capacitor banks), and discharge current-limiting reactors, are also covered.