What is the purpose of a commutator on a generator?

• A. It converts AC into DC (mechanical means)
• B. Rectifies DC into AC
• C. Stores energy
• D. Increases voltage

Answer: (A)

The commutator acts as a mechanical rectifier. As the armature spins in the magnetic field, it generates alternating current in the windings. The commutator, a split ring connected to the coil ends, reverses the connection to the external circuit every half turn, while the brushes stay in contact with the segments. This keeps the current delivered to the load in one direction, producing DC. The other options don’t fit because rectifying DC into AC isn’t done by a generator’s commutator, storing energy isn’t its role, and simply increasing voltage comes from field strength or speed, not the commutator’s function.