difference between relay and circuit breaker

The Relay is a switching and sensing device, but the Circuit breaker is an isolating or disconnecting device. Relays operate on low power input voltage. ... The Relay is used to control or select one among many circuits, whereas Circuit Breaker is one per circuit. Relay acts an electrical amplifier for discrete signal.

BASIS	RELAY	CIRCUIT BREAKER
Principle	The Relay is a switching device which gives a signal to the circuit breaker as soon as the fault occurs in the power system.	Circuit breaker breaks the circuit automatically when receives the signal from the relay.
Working	The Relay does not break the contact. It only senses the error and send the signal to the circuit breaker.	It breaks the circuit contacts.
Type of device	The Relay is a switching and sensing device.	The Circuit breaker is an isolating or disconnecting device.
Voltage	Relays operate on low power input voltage.	The Circuit breaker is an automatic on load device.
Usability	It is used to control or select one among many circuits.	It uses one per circuit.
As an amplifier	Relay acts an electrical amplifier for discrete signal.	Circuit breaker does not act as an amplifier.

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The detailed description of Difference Between Relay and Circuit Breaker is described below.

• The Relay is a switching device which gives a signal to the circuit breaker as soon as the fault occurs in the power system. Circuit breaker breaks the circuit automatically when receives the signal from the relay.
• The Relay does not break the contact. It only senses the error and send the signal to the circuit breaker where as Circuit Breaker breaks the circuit contacts.
• The Relay is a switching and sensing device, but the Circuit breaker is an isolating or disconnecting device.
• Relays operate on low power input voltage. The Circuit breaker is an automatic on load device.
• The Relay is used to control or select one among many circuits, whereas Circuit Breaker is one per circuit.
• Relay acts an electrical amplifier for discrete signal. Circuit breaker does not act as an amplifier.