Brush spacing method quartering is used to check what?

• A. Scribing
• B. Quartering
• C. Calibrating
• D. Measuring

Answer: (B)

Brush spacing method quartering is about aligning the brushes to the correct electrical angles relative to the pole pitch in a DC machine. The idea of quartering is to divide the circumference into four equal electrical segments so each brush sits a quarter cycle away from the next. This spacing ensures that commutation occurs at the proper instants, reducing sparking and excessive wear on the brushes and commutator. In practice, you set reference marks on the brush gear, rotate the rotor to bring the marks into alignment at four equal points, and verify that the actual brush positions match the required quarter-pole spacing. Scribing, calibrating, and measuring describe other actions, but this method specifically checks that the brush positions are correctly quartered for proper commutation.