Give Three possible electrical reasons why a three-phase induction motor will not run when it is started ??

1- The winding burnt 

2- loose on one or more in supplying phases

3-One or more of the winding coils is open 

1) Check power weight of induction motor.

2) Motor shaft key is missing or damaged.

3)  check all switches or motor starter  points or smell coil is damaged.

1- Winding is short due to burn out.

2- Winding is open due to cuts.

3- Supply is open due to breakage of supply wire.

4- Slip ring is not properly providing the current to the rotor.

1) Locked Rotor.

2) Stall

3)Not fulfilling Start permissive.

4) Control fuse burnt.

5) Motor Burnt.

6) All3 or1 Power Fuse burnt

7)Motor tripped &  tried to start without Overload resetting.

8) Control cable loose/open/burnt

9)Motor Short circuited/ got Earthed

10) Push button Element got faulty / loose, Dust inside Push botton

Testing & troubleshooting 

This is my first step to cheek wiring. 

Second cheek the motor winding to the ma-gar meter.

after all will go to work shop open the motor cheek to the bearing.

where is missing to repair to maintenance. 

1. Motor Control Center in Test position.

2. Internal protection activated (temperature by either true of faulty probes signal).

3. A lock-out it's present giving a past fault, and a timer it's counting back.

1)check all the three phases ara available

2)check the control supply present

3)wheather the motor tripped on overload

If power supply is present then

1. Open or short circuit in satator
2. Open or short circuit in rotor
3. Meachnically over load

Before any of the suggestions given below, check the starting system overload if it is tripped. Then check the phase to phase voltage at the Magnetic contactor/overload output.