What may cause brush sparking in a DC...

What may cause brush sparking in a DC...

Question 1 of 270705eccefa3bacbc34ba4d48092

What may cause brush sparking in a DC generator during commutation?

Question 1 of 27070

Q

What may cause brush sparking in a DC generator during commutation?

🔍 Key Concepts

• Commutation in a DC generator and what is happening at the brushes when the current reverses in the armature coils • The mechanical position of the brushes relative to the neutral plane (magnetic neutral axis) • How mechanical vs magnetic core issues (eddy currents, hysteresis) affect operation differently

💭 Think About

• Ask yourself: which option directly affects the correct transfer of current between commutator segments at the instant of commutation? • Consider whether each choice is mainly an internal magnetic loss in the iron core or something that changes how the brushes physically contact the commutator. • Which condition would most likely cause uneven contact or arcing at the brush–commutator interface during operation?

✅ Before You Answer

• Separate choices that deal with iron losses in the core (eddy currents, hysteresis) from those that deal with brush–commutator geometry or pressure. • Think about the effect of too much vs. incorrect placement of brushes: does extra pressure alone cause sparking, or does incorrect position cause worse commutation? • Visualize the brushes on the commutator: which option directly relates to their correct alignment with the magnetic neutral plane, where sparking should be minimal?