To check the brake, a measurement is made of the air gap between magnet body and anchor plate, as well as the brake lining thickness.

The illustrations show the check on the air gap and brake lining thickness on a drive of size 80. Checks on larger or smaller drives are carried out in the same way.

Overview:

Due to the wear of the brake lining as the motor is braked, the brake rotor gradually becomes thinner. The anchor plate is thereby pressed ever further toward the brake rotor during braking and the air gap thus becomes wider. If the air gap has reached its maximum width, a gap limiter prevents the anchor plate from being pressed any further, thus ensuring that the anchor plate is reliably ventilated. When the gap limiter is employed, the braking effectiveness gradually lessens.

This is the point at which the air gap must be readjusted at the latest. If the minimum lining thickness has been reached, the brake rotor must be replaced.

If the width of the air gap is within the permitted range but usage behaviour leads to the expectation that the air gap will be wider than permitted before the next regular inspection, the air gap must be readjusted now.

   Unscrew and remove screws (4x).

   Take off the fan cover.

  Insert the feeler gauge next to one of the hexagon head screws in the air gap between magnet body and anchor plate and measure the distance.

   If the air gap has reached the maximum width of the operating range, adjust the brake. See Adjusting the air gap at the brake on the drive with the helical gear unit.

If the width of the air gap is within the permitted range but usage behaviour leads to the expectation that the air gap will be wider than permitted before the next regular inspection, the air gap must be readjusted now.

   Repeat the steps for all hexagon head screws (3x).

   Clean the entire brake with compressed air.

   Check the thickness of the brake lining with a calliper.

   If the brake lining is thinner than permitted, replace the brake rotor. See Replacing brake rotor and anchor plate on drive with the helical gear unit.

   Attach fan cover.

   Tighten screws (4x).