SDZ dry two-piece series loss of power brakes, power failure by the spring force, resulting in brake torque, brake torque when power is zero. Loss of power brake often directly supporting the motor, widely used in packaging, handling, printing, rolling, general industrial machinery is maintained to stop and positioning. The product is low power consumption, high speed allowable, agile, easy to wear and tear after the air-gap adjustment. Required excitation voltage 24VDC, 170VDC users need to special order. The units provide users with a variety of excitation voltage transformers.