How can you find that a motor is AC or DC without any aid?

How can you find that a motor is AC or DC without any aid?

AC motor : 

1. There are 6 terminals of the AC motor with all equal sizes.

2. There are cooling strips in the AC motor.

3. The cooling fan is outside of the AC Motor.

DC motor 

1. DC Compound Motors also has 6 terminals but 4 of them are of the same size and 2 of the terminals are always smaller than the other four.

2. There are no cooling strips in DC Motor.

3. The cooling fan is inside the DC Motors.

- Synchronous motors have 5 terminals of which 3 of them are used to connect three phases (AC) and 2 of them are for rotor excitation and provided with DC supply.

- If a motor has 4 terminals then it will lie in the

category of DC Motors.

- If a motor has 3 terminals then it will bea

Y-connected AC Motor and its windings are connected in star internally.

-If a motor has 2 terminals then it will bea

single-phase induction motor