Lenze DSD - Manual (Page 328)

11 Drive Dimensioning
11.3 Mechanical brake selection
328
Lenze · Drive Solution Designer · Manual · DMS 4.2 EN · 12/2013 · TD23
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11.3.3 Dimensioning criteria
For the dimensioning of the motor brake as holding brake, the following parameters are taken into
consideration:
• Moment of inertia of the brake
• Holding torque
• Safety factor
• Electrical connection
• Installation feasibility with regard to the motor
The following is not taken into consideration:
• Twin rotor disc brakes of the BFK458 series
• Operating times
• Thermal dimensioning for cyclic braking processes
• Service brake: wear calculation for braking during operation and emergency stop.

Danger!
Falling loads in the case of vertical conveyors (angle > 45°) such as hoist drives.
In DSD you cannot dimension service brakes, but only holding brakes.
Protective measures:
• In order to ensure that the brake works safely, carry out all tests required manually.
• Dimension brakes for vertical conveyors with a safety factor ≥ 2.
• Do not use a permanent magnet holding brake (PMB) as service brake. It cannot brake
safely, since the braking torque decreases significantly at higher speeds.
• Additionally use a redundant brake assembly outside the motor, or a motor with a
spring-applied brake (BFK).