Question

What will happen if DC motor is used without starter?

(a) Heavy sparking at brushes

(b) It’ll start smoothly

(c) Will not start at all

(d) Depends on load

I got this question in examination.

This key question is from Starting of DC Motors in chapter DC Motors of DC Machines

Answer 1

The correct answer is (a) Heavy sparking at brushes

For explanation I would say: It would cause intolerably heavy sparking at the brushes which may destroy the commutator and brush-gear. Sudden development of large torque will cause mechanical shock to the shaft, reducing its life. Such heavy current cannot be generally permitted to be drawn from the source of supply.