AEE72-Electrical Installations & Design-Module 7- Video 5 &6

Interrupts power to the motor circuit in case of short circuits or ground faults

• Overcurrent protection

• Overload protection

Which one of the below is not an application of Over-current

• Fuses

• circuit breakers

• Contactors

Protects the motor from damage from mechanical overload conditions when it is running,when there is an excessive rise in temperature in the motor windings.

• overload relays and thermal overloads

• Relay

• Push-button

• Contactor

A type of Motor control category used to run or moved the motor to short distances for positioning or alignment purpose

• Jogging

• Sequence control

• Speed control

A type of Motor control category where a predetermined sequence is set for the motor circuit to operate

• Jogging

• Sequence control

• Speed control

Is this starter circuit considered as ?

• A reduce voltage starting method

• An across the line starting method (direct online starter)

Name the device with the label X

• 3 phase supply

• 3-poles Circuit Breaker (CB)

• Magnetic contactor

• Thermal Over Load (OL)

In which of the following devices does an overload current cause the bi-metal strips to bend and change position of the auxiliary contacts?

• Magnetic overload relay

• Thermal overload relay

• Miniature circuit breaker

• Control Relay

• Limit switch

Which of the following is an example of ‘Across the line starter’?

• Primary resistance starter

• Secondary resistance starter

• Autotransformer starter

• Series inductance starter

• Magnetic starter

the difference between Relays and Magnetic Contactors is

• Magnetic contactor has higher current ratings

• cannot be controlled remotely

• more advanced and rigid

• It has Normally open and normally closed contatcs