Page 208 - Electrician - TT (Volume 1)

ELECTRICIAN - CITS

Effects of armature reaction

• MNA is shifted
• The path of the magnetic field is distorted
• The flux concentrates on trailing pole tip
• Effectively the field is demagnetised as the leading pole tip is weakened

Problems due to armature reaction
• Causes sparking as MNA is shifted
• EMF generated is reduced as field is weakened
• Causes more wear and tear of brushes.
• Efficiency is reduced

• Reduced capacity
• Remedy for armature reaction Making slots in TPT
• Rarely used as only one DOR can be use
Remedy for armature reaction

• Staggering

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CITS : Power - Electrician & Wireman - Lesson 30-37