🔍 Key Concepts

• Torque–speed characteristics of different DC motor types • How a series-wound DC motor behaves with sudden loss or reduction of load • Why runaway speed can be dangerous in belt-driven systems

💭 Think About

• Think about which DC motor type will increase speed dramatically if the mechanical load suddenly decreases, such as if a belt slips or breaks. • Consider which motor type has its field strength directly dependent on the armature current, and what happens to field strength when the load gets lighter. • Ask yourself: in a belt-driven system where the belt might slip or break, which motor design could overspeed and damage itself or connected equipment?

✅ Before You Answer

• Verify which DC motor type has the weakest inherent speed regulation and is most prone to overspeed when lightly loaded. • Check which winding arrangement causes field current and armature current to be the same, and what happens to both when the load drops. • Confirm which motor types (shunt, compound, permanent magnet) have better speed control and are therefore more suitable for belt-driven loads.