Brush Pressure

Carbon Brush Pressure

The recommended brush pressure is expressed in units of cN/cm2. The optimum brush pressure will be determined by the brush grade and design of the brushes to be applied, suited to the operating condition of the machine. An incorrect or un-even brush pressure can result in damage to the commutator or slip ring, excessive brush wear, vibration and can lead to poor commutation condition. The temperature of the commutator or slip ring may also be affected drastically.

It is therefore very important to check on a regular basis the brush holders for the correct pressure in order to optimise the performance of the carbon brushes. This can be done by using a spring balance specially designs for that purpose. We recommend the following brush pressure:

• Stationary Comm. Machines
• Slip Ring Motors
• Traction Motors
• Turbo Generators



180-200 cN/cm²
200-250 cN/cm²
300 to 500 cN/cm²
130 to 150 cN/cm²