Question

Aluminium is not used as winding wire for the armature of d. c. machine because
1. Aluminium has low resistivity
2. Of large winding space required by Aluminium conductor
3. Of low thermal conductivity of Aluminium
4. Of high cost of Aluminium

Answer 1

Correct Answer - Option 4 : Of high cost of Aluminium

Aluminum is not used as winding wire for the armature of a dc machine because a large winding space is taken by aluminum conductors and creates jointing problems. Copper is best used as winding wire for the armature of a dc machine.