Аннотация
In the article the author presents the developed protections with their design, which are an alternative to traditional current protections, which at the same time have a resource-saving effect. Creation of resource-saving devices of relay protection of electrical installations against short circuits without the use of metal-intensive measuring current transformers (CT) with metal cores was started in the 60s of the last century, which remain relevant to this day. The scientific novelty of the work consists in further development of the theory of construction of protections on inductance coils and reed switches, based on the measurement of induction of magnetic fields in various modes and points inside the cell of the complete switchgear (CS). In such protections inductive coil and reed switch act simultaneously as a current (voltage) sensor and measuring device protection, responding to the magnetic field generated by currents in the current-carrying busbars of the protected electrical installation or cell. To perceive the magnetic field, the inductance coil or reed switch is installed close to the current-carrying busbars, observing the minimum permissible distance. The purpose of the study is to develop a new resourcesaving protection for various electrical installations, connected to the switchgear cell, as well as separately standing new resourcesaving protection, made on inductive coils and reed switches. At the same time, for example, in the protection with regulation of tripping settings there is a possibility of their remote regulation without disconnection of the connected electrical installation.