In a series-wound machine, how is the armature connected with the field winding?

• A. The armature is connected in parallel with the field winding
• B. The field winding is connected in parallel with the supply
• C. The device uses a separate excitation for field
• D. The armature is wired in series with the field winding

Answer: (D)

In a series-wound machine, the armature is connected in series with the field winding, so the same current flows through both. That means the field excitation follows the armature current: as load increases and more current flows, the magnetic field strengthens, producing high starting torque. This arrangement gives strong torque at startup and causes the speed to vary a lot with load, since the field strength is not independently fixed. Open-circuiting the field or removing the load can lead to dangerous speed changes, which is why these machines are chosen for applications needing high starting torque but with controlled loading.