If the brake lining on the drive is thinner than permitted, then the fan blade with brake lining must be replaced.

When replacing the fan blade with brake lining, it is recommended that the anchor plate be replaced as well.

   Take off the fan cover.

   Hold the fan blade firmly and unscrew the self-locking nut.

   Remove the fan blade with brake lining.

When replacing the fan blade with brake lining, it is useful to replace the anchor plate as well. If the anchor plate is not to be replaced, this section may be skipped.

   Screw the collar screws (2x) out.

●   The anchor plate is pressed away from the motor. It is tensioned by a spring.

   Remove the anchor plate. Ensure that the compression springs do not fall out.

If the O-ring, plate springs, compression springs or the feather key are missing or damaged, they must be replaced. If the components are in a good condition, this section may be skipped.

Removing damaged components:

   Pull the plate springs and feather key from the motor shaft.

   Pull the O-ring and compression springs from the brake bearing shield.

Replacing components:

   Assemble the plate springs as shown in the illustration.

   Push the plate springs onto the motor shaft.

   Insert the feather key.

   Place the O-ring into the groove on the brake bearing shield.

   Insert the compression springs.

   Insert new anchor plate and press it against the compression springs.

   Clean the collar screw thoroughly.

The collar screws were previously bolted with a thread lock coating or a thread lock. The residues must be completely removed before the collar screw may be used again.

   Apply thread lock (medium-strength) to the thread of the collar screw.

When doing so, ensure that not too much thread lock is applied so that it does not emerge out of the thread.

If a thread lock coating has been applied to the collar screw, no thread lock may be used!

   Tighten the collar screws (2x). 5 – 7 Nm.

   Slide the new fan blade with brake lining onto the motor shaft.

   Screw the new self-locking nut loosely to the motor shaft.

Do not use the old self-locking nut.

   Hold the fan blade firmly and screw the self-locking nut until hand-tight. The fan blade should just be tight enough that it almost cannot be turned.

●   The air gap is now set to 0 mm. This serves as the starting point for the following setting.

The self-locking nut is now released in order to optimally adjust the air gap of the brake. The releasing of the self-locking nut is oriented to the individual segments of the fan blade.

   Hold the fan blade firmly and release the self-locking nut by the amount of two and one half segments of the fan blade.

●   The air gap is now set to the optimal width of 0.4 mm.

To make sure, check that the distance between the brake bearing shield and the anchor plate (reference gap) is between 3.1 mm and 3.7 mm. See Inspecting the brake on the drive with the helical gear unit.

   Attach fan cover.