Carbon brushes exist since 1870 when the first collector machines were developed.
Facing the advancing development of the DC drive loaded with brushes towards the concepts without brushes you should think that carbon brushes are a dying product. But there is no tonic like reading your own obituary. Even AC drives without brushes often do need a carbon brush for the dissipation of the capacitive shaft currents.

Improved formulas, matched impregnation and intelligent solutions in connection with the brush holder, life time of carbon brushes have increased in the past years and due to this the reputation of the DC motor has improved accordingly.  A brush service life of 20.000 hours is no problem anymore in many applications.

More than 500 different standard materials out of 10 materials categories are offered by named carbon producers to solve the problems of their customers. Year by year it becomes even more. Combined with the various brush versions, the user is faced with an enormous choice of product variety, hardly to overlook, but thus offering the chances of a customer orientated or application orientated solution of the problem.  In close teamwork with the motor producers the optimal solution is filtered out.

Carbon brushes are ceramic carbon materials, which are processed out of carbonic raw materials like coke, graphite, carbon black, tar pitch or resin. Metals are creating the adequate voltage drop in brushes e.g. for low voltage motors.

The carbon materials suiting the respective applications are produced in various processing steps using heat treatments up to 3000 °C. After-treatments with metals, oil or waxes can optimize the running performance. The shape of the brushes e.g. block- or twin brush can have besides others a major effect on the commutating properties of the brushes. The whole production process can take up to one year.

In the course of the last decades the carbon brushes were faced with new challenges.
Besides the obvious control of the commutating properties on DC motors, difficult environmental conditions like chemical influences, high or low air humidity or load problems are the focus of attention nowadays.

In times of reduction of maintenance staff, the interpretation of commutator- or ring surfaces and the carbon brushes themselves become increasingly important. When applied correctly carbon brushes are good indicators for the condition of the machine respectively are leading to remedial measures.