Dc motor controller, as a kind of industrial machinery, use more convenient, one of the important parts is to brush, in long time use brush wear would happen. If wear seriously will affect the use of the motor controller, so everyone should notice when change the brush. Below small make up take you to understand it. 1. Because of the different types of brush in hardness and current density is different, so choose the brush is to choose the same type of brush. 2. When change the double brush, attention should be paid to the order, prevent the brush to beat, affect the reversing. 3. The new brush need grinding as the same as the old brush radian and the size. 4. Pay attention to adjust the pressure of the brush, and brush size to fit. 5. Pay attention to the brush contact with armature must have the obvious, but do not force tuck it in. Above is change the brush dc motor controller is to pay attention to matters.