Carbon Graphite Brushes
Graphite is mixed with pitch or resin, pressed and then baked. Patina and commutation properties are good, but current carrying strength is weaker than electrographite brushes. Thyristor fed or flat machines, small DC motors, micaceous collectors.
In large cranes (cement, iron-steel, harbour works) current busbars are produced with hard carbon class raw materials. These products provide ideal strength especially for aluminium profile busbars.