Hoist Mechanical Brake - GE AF-650 GP Design And Installation Manual

Application Set-Up Examples
6 6
Illustration 6.23 Mechanical Brake Control in Open Loop
In hoisting/lowering applications, it must be possible to
control an electromechanical brake.
Step-by-step description
•
To control the mechanical brake, any relay output
or digital output (terminal 27 or 29) can be used.
If necessary, use a suitable contactor.
•
Ensure that the output is switched off as long as
the frequency converter is unable to drive the
motor, for example due to the load being too
heavy or as the motor has not been mounted yet.
•
Select [32] Mechanical brake control in parameter
groups E-2# before connecting the mechanical
brake.
•
The brake is released when the motor current
exceeds the preset value in
parameter B-20 Release Brake Current.
•
The brake is engaged when the output frequency
is less than the frequency set in
parameter B-21 Activate Brake Speed [RPM] or
parameter B-22 Activate Brake Speed [Hz] and only
if the frequency converter carries out a stop
command.
72
NOTICE
For vertical lifting or hoisting applications, it is
recommended to ensure that the load can be stopped if
there is an emergency or a malfunction of a single part
such as a contactor,.
If the frequency converter is in alarm mode or in an
overvoltage situation, the mechanical brake cuts in.
NOTICE
For hoisting applications, make sure that the torque
limits in parameter F-40 Torque Limiter (Driving) and
parameter F-41 Torque Limiter (Braking) are set lower than
the current limit in parameter F-43 Current Limit. Also it is
recommendable to set parameter SP-25 Trip Delay at
Torque Limit to "0", parameter SP-26 Trip Delay at Drive
Fault to "0" and parameter SP-10 Line failure to "[3]
Coasting".

6.6.4 Hoist Mechanical Brake

The General Purpose Drives AF-650 GP features a
mechanical brake control designed for hoisting
applications. The hoist mechanical brake is activated by
option [6] in parameter F-25 Start Function. The main
difference compared to the regular mechanical brake
control, where a relay function monitoring the output
current is used, is that the hoist mechanical brake function
has direct control over the brake relay. This means that
instead of setting a current for release of the brake, the
torque applied against the closed brake before release is
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