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_______________┬а motor is used in the mixer/blender.
Repulsion Motor
Shaded pole motor
Capacitor start capacitor run motor
Universal Motor
Universal Motor
Universal motors are high-speed, series-wound motors designed to operate on both AC and DC supplies. They produce a high starting torque and high operating speed (typically 3,000 to 20,000 RPM), making them ideal for small domestic kitchen appliances such as food mixers, blenders, and grinders.
Universal motors are high-speed, series-wound motors designed to operate on both AC and DC supplies. They produce a high starting torque and high operating speed (typically 3,000 to 20,000 RPM), making them ideal for small domestic kitchen appliances such as food mixers, blenders, and grinders.
TтИЭI2 тАФ Torque produced is proportional to the square of current (high starting torque)
NтИЭTтАЛ1тАЛ тАФ Inverse speed-torque characteristic of series motor
When supplied with single-phase AC or DC, the armature current and main field current reverse direction simultaneously every half-cycle. Because the developed electromagnetic torque is proportional to the product of field flux and armature current (TтИЭ╬жIaтАЛ), the torque remains unidirectional regardless of supply polarity reversals.
Universal motors run at very high speeds under no-load conditions and automatically slow down as load increases.
The armature and field windings are connected in series.
Commutation causes spark formation, so carbon brushes and commutators require periodic maintenance.
High starting torque capable of handling tough food loads
Compact size with a very high power-to-weight ratio
Can run on both single-phase AC and DC power source
Produces radio frequency interference (RFI) due to brush sparking
High operational noise levels at elevated speeds
Requires maintenance due to wear and tear of carbon brushes
Kitchen food mixers, blenders, and juicers
Portable power tools like electric drills and angle grinders
Vacuum cleaners and sewing machines
Option A (Repulsion Motor): Used in applications needing very high starting torque with constant speed, like air compressors.
Option B (Shaded Pole Motor): Low starting torque, used in small fans and blowers.
Option C (Capacitor Start Capacitor Run Motor): High starting torque and high efficiency, used in refrigerators and air conditioners.
D is correct тАФ Universal motors deliver the high starting torque and high operating speeds (up to 20,000 RPM) required by food mixers and blenders.
Remember for exams: Universal motors have the highest speed among all single-phase motors and can dangerous run away at no-load, so they are mostly direct-coupled or gear-driven to loads.