Functional description of the static brake test
WARNING
Performing the brake test on a damaged brake or machine can lead to undesired movement of the machine.
Severe or fatal injuries.
- No person may be present in the hazard zone during an active brake test.
- The mechanics of a hoist must be designed for a possible fall using buffers, for example.
- The brake test must be performed with the machine in a suitable test position.
The Safe Brake Test (SBT) function is a static brake test for horizontal and vertical applications. The static brake test diagnoses whether the brake that is being tested can maintain a static test torque that is applied against the applied brake.
The brake test takes place in several stages. This makes it possible to clearly detect the numerous potential errors and minimize the effects of the system on the result of the brake test. To begin with, the drive carries out a parameterizable movement. The static brake test must be called up from a suitable test position that allows the machine to make this movement.
During startup, the settings must be made so that the applicative load torque and the proportional motor torque together give the required test torque. A static load torque acting upon the drive due to the own weight of the system, for example, must be taken into consideration. Before calling up the brake test and during the brake test, it must be ensured that the load conditions are steady during startup in accordance with the settings so that the brake is tested correctly.
The brake test records torques via the inverter and specifies torques to the inverter as setpoints. The torques are not evaluated from a safety technology point of view. The accuracy of the torque recording corresponds to the accuracy of the inverter.
When executing the brake test, movements are safely monitored for adherence to the limit values that have been set by the MOVISAFE® CS..A safety option.
In safe brake systems with more than one brake, the static brake test must be carried out separately for each brake. The brake test described here can test one or 2 brakes. With 2 brakes, the brakes can be tested separately with the same test parameters or with adapted test parameters. One brake is applied for testing, whereas the second brake remains released.
