Motor control Week 09

What is the purpose of a relay?

• To amplify electrical signals

• To switch electrical circuits on and off

• To filter electrical noise

• To measure electrical resistance

What are the maximum voltage and current rating of a relay?

• Voltage rating

• Current rating

• Contact rating

• Coil rating

What is the purpose of a latching relay?

• To switch electrical circuits on and off

• To hold a circuit in a specific state

• To amplify electrical signals

• To filter electrical noise

When the relay coil is energized, there is a time delay before the contact closes.

• On delay NC contact

• On delays NO contact

• OFF delay NC contact

• OFF delays NO contact

When the relay coil is de-energized, there is a time delay before the contact opens.

• On delay NC contact

• On delays NO contact

• OFF delay NC contact

• OFF delays NO contact

MCB stands for.

• Miniature contact breaker

• Main circuit breaker

• Miniature circuit breaker

• Mini contact breaker

A relay is used to.

• Break the fault current

• Sense the fault

• Sense the fault and direct to trip the circuit breaker

• All answers are correct

What is the main component of a relay?

• contacts

• coil

• diode

• capacitor

How does a relay work?

• By using a mechanical switch

• By using a semiconductor technology

• By using an electromagnet to activate or deactivate a switch or circuit

• By using a resistor to change the current

What are the maximum voltage and current rating of a contactor?

• Voltage rating

• Current rating

• Contact rating

• Coil rating