Danfoss iC7 Motion Series Application Manual page 239

Application Guide | iC7 Series Motion
Default Value:
Unit: -
Mechanical Brake Control (Menu Index 5.12)
6.6.13
Mechanical Brake Control Overview
6.6.13.1
The feature controls opening and closing of the mechanical brake and ensures the smooth transition of load between drive and
mechanical brake. The mechanical brake holds the load when the drive is not running. The mechanical brake can be closed or released
by controlling the torque, speed, and position. The feature supports the following load types:
Unidirectional load: Typically used in scenarios when the load moves in the same direction such as in conveyors, winches, crane
l
applications.
Bidirectional load: Typically used in scenarios when the direction of the load is not known during startup, such as in elevator
l
applications.
The mechanical brake control supports the following functions:
2 channels for mechanical braking feedback to offer further protection against unintended behavior resulting from broken cable.
l
Monitoring of mechanical braking feedback throughout the complete cycle. Monitoring helps to protect the mechanical brake,
l
especially if more drives are connected to the same shaft.
No ramp-up until feedback confirms that mechanical brake is open.
l
Improved load control at stop. If the value of the delay is too low, a warning is issued and the torque is not allowed to ramp down.
l
The transition when motor takes over the load from the brake can be configured. Parameter Release Bandwidth can be increased to
l
minimize the movement.
To achieve smooth transition, change the setting from speed control to position control during the changeover.
Starting with mechanical brake
The motor must be primed by gradually applying a holding torque against the brake so that the torque step is minimized when the
l
brake is released.
When the configured torque is applied and priming time has passed, the brake is released. The torque and priming time is set via
l
parameters 5.12.2.2 Brake Priming Torque and 5.12.2.4 Brake Priming Time. After priming, the brake is released.
There is a physical delay between the electrical release of the brake and the physical release of the brake. This is referred to as brake
l
release time and is set via the parameter 5.12.2.6 Brake Release Time. When this happens, the load is shifted from the mechanical
brake to the motor instantaneously.
Stopping with mechanical brake
When stopping, the mechanical brake control monitors the motor speed and ramps down to 0 speed to close the brake.
l
When closing speed is reached, the brake is activated, and the motor is held at 0 speed while the brake physically closes.
l
When the brake is closed, torque is ramped down to 0, gradually shifting the load from motor to brake.
l
The following images represent the different functions of Mechanical Brake Control.
© 2023.11
Parameter Type: Selection
Data Type: UINT
Parameter Number: 1087
Access Type: Read/Write
AB318753549016en-000301 / 136R0284 |
237