The reactance relay is a high-speed relay. This relay consists of two elements an overcurrent element and a current-voltage directional element. The current element developed positive torque and a current-voltage developed directional element which opposes the current element depending on the phase angle between current and voltage. Reactance relay is an overcurrent relay with directional …
Definition: The relay whose working depends on the distance between the impedance of the faulty section and the position on which relay installed is known as the impedance relay or distance relay. It is a voltage controlled equipment. The relay measures the impedance of the faulty point, if the impedance is less than the impedance …
Distance protection relay is the name given to the protection, whose action depends on the distance of the feeding point to the fault. The time of operation of such protection is a function of the ratio of voltage and current, i.e., impedance. This impedance between the relay and the fault depends on the electrical distance …
Definition: The overcurrent relay is defined as the relay, which operates only when the value of the current is greater than the relay setting time. It protects the equipment of the power system from the fault current. Depending on the time of operation the overcurrent relay is categorized into following types. Instantaneous Overcurrent relay Inverse …
The thermal relay works on the principle of the thermal effect of electrical energy. The bimetallic strips, heating coils and the current transformers are the important parts of the thermal relay. The current transformer supplies the current to the coils of the heater. The thermal energy of the heater coils heated the bimetallic strips. The …
The relay may be defined as an electrical device interposed between the main circuit and the circuit breaker in such a manner that any abnormality in the circuit acts on the relay, which in turn if the fault is dangerous then it causes the circuit breaker to isolate and so to remove the faulty element. …
Protective relay work as a sensing device, it senses the fault, then known its position and finally, it gives the tripping command to the circuit breaker. The circuit breaker after taking the command from the protective relay, disconnect the faulted element. By clearing the fault fast with the help of fast-acting protective relay and associated …
Definition: The relay which does not contain any moving parts is known as the static relay. In such type of relays, the output is obtained by the static components like magnetic and electronic circuit etc. The relay which consists static and electromagnetic relay is also called static relay because the static units obtain the response and …
Definition: The Buchholz relay protects the transformer from internal faults. It is the gas actuated relay. The Buchholz relay is placed between the main tank and the conservator. Such type of relay is used in the transformer having the rating higher than 500KVA. It is not used in small transformer because of economic consideration. Working …
The HRC fuse element carries the short circuit or faults current for the specific interval of time. And if the fault removes in that specific period then the fuse element remains safe and it does not melt or breaks. The fuses element is kept inside the airtight container. The HRC fuse has inverse time characteristic, i.e., if …
