Select the relay type that compares currents at two points to detect faults within a protected zone.
Differential relay
The question asks for the type of relay that compares currents at two points to detect faults within a protected zone. To answer this, we need to understand the function of each relay type mentioned in the options:
- Inverse Time Overcurrent Relay: This type of relay operates when the current exceeds a predetermined value and the operation time is inversely proportional to the magnitude of the current. It does not typically compare currents at two different points.
- Distance Relay: This relay measures the impedance between the protection relay and the fault location. It is used mainly for line protection and does not directly compare currents at two different points.
- Differential Relay: The primary function of a differential relay is to compare the current entering and leaving a protected section. It operates if there is a difference between these currents, indicating a fault within the protection zone.
- Instantaneous Overcurrent Relay: This relay operates immediately when the current exceeds its setting, without intentional delay. It also does not compare currents at two different points.
From the above explanation, we can see that the differential relay is specifically designed to compare currents at two points to detect electrical faults within a protected zone. This type of relay is used in systems where precise fault detection is crucial, as it ensures that only internal faults within the defined zone cause a trip.
Conclusion: The correct answer is Differential Relay.
Similar Questions
A control circuit uses a timer relay to switch ON a load after a set delay. If the load energizes immediately when the circuit is powered, what is most likely wrong?
In a control panel, why is it necessary to select a contactor with a higher making capacity than the running current of the connected load?
Important Questions from Relays and Voltage Regulators
A control circuit uses a timer relay to switch ON a load after a set delay. If the load energizes immediately when the circuit is powered, what is most likely wrong?
In a control panel, why is it necessary to select a contactor with a higher making capacity than the running current of the connected load?
