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 power systems 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 filter reactors, shunt capacitor reactors (used with shunt capacitor banks) and discharge current limiting reactors (used with series capacitor banks), are also covered.