Product Description:

The 03.38.13N-34CU is a normally closed, spring-applied brake manufactured by KEB within the Combistop Spring Brakes series. It is intended to hold or stop rotating machine elements whenever power is removed, ensuring axis security in lifts, conveyors, and rotary indexers. Energizing the coil releases the rotor so motion can resume. De-energizing the coil allows the internal springs to press the rotor against the friction lining, producing the holding force needed for industrial automation tasks.

An angular deviation limited to 0.04 mm keeps the hub concentric with the driven shaft, and mounting eccentricity is restricted to 0.4 mm for uniform lining pressure. When DC voltage is supplied, the armature begins to lift after a 15 ms delay and reaches full stroke within the 30 ms engagement time. The coil consumes 30 W of operating power, which affects power supply sizing and enclosure heat load. A nominal air gap of 0.2 mm is preset at the factory; if this clearance grows, torque declines and response slows. Under rated conditions, the brake develops 10 Nm of braking torque. It is fastened with three M5 × 45, Class 8.8 screws, which provide the clamping strength required to resist spring force and dynamic loads.

The friction lining may wear by up to 1.5 mm before adjustment is necessary; exceeding this limit reduces release travel. The lining must not be allowed to thin below 6.5 mm to maintain its heat absorption capacity during repeated stops. If an inspection finds that the operational air gap has widened to 0.5 mm, shims or the hand-release screw can restore the original setting. A hand-release distance of 1.0 mm provides the clearance required for manual operation. The 1.5 mm hub counterbore also helps machine builders allocate adequate space for hub seating within compact machine frames.