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Carbon brush problem solutions for carbon brush motor

Brushed DC motor and Brushed AC motor is driven by the carbon brush and commutator pole contact to continue to rotate, so the brush and commutator pole friction is inevitable, also because of the continuous sliding friction, some faint spark is normal.But sometimes, especially after a new brush is replaced, the spark will be bigger, the brush wear will be faster, in serious cases, will burn out the rotor.
Causes of excessive spark of carbon brush and solutions:
(1) The carbon brush is not the original factory, and the carbon brush is too hard or the brand does not meet the requirements. Solution: replace the original factory carbon brush
(2) Uneven spring pressure on the carbon brush of Brushed DC motor and Brushed AC motor. Solution: adjust the spring pressure appropriately to keep the pressure of each carbon brush balanced
(3) The brush grip becomes loose. Solution: tighten the brush grip bolts so that the brush grip and the commutator surface are parallel
(4) The distance between brush grip and commutator surface is too large. Solution: Adjust the distance between brush grip and commutator, generally 1~3mm
(5) Bad contact between carbon brush and commutator. Solution: The carbon brush may be worn too short, and the contact surface of carbon brush may be ground or replaced with a new carbon brush
(6) Improper coordination between carbon brush and brush grip. Solution: not too tight or too loose, to ensure that the brush in the hot state can freely slide in the brush grip, too tight can use sandpaper to appropriate carbon brush sand, too loose to replace a new carbon brush.
(7) If the mica between the commutator plates is not clean, use the broach to remove the remaining mica. Solution: mica protruding between the commutator plates and fine turn the commutator
(8) The center of the brush holder is not in the right position. Solution: move the brush holder and choose the best location of the spark
(9) Short circuit of commutator coil. Solution: rewind the coil
(10) Armature winding short circuit. Solution: disassemble the Brushed DC motor or Brushed AC motor, check the armature winding, use millivolt meter to find the open circuit, if it cannot be welded, will be rewound.If conditions do not exist, replace the new armature.