Danfoss VLT AutomationDrive FC 300 Design Manual page 153

FC 300 Design Guide
Enabled (not at stop)
Enabled
Function:
The Over-voltage Control is selected to reduce the
risk for the drive to trip by an overvoltage on the
DC link caused by generative power from the load.
Enabled (not at stop), means that OVC is active
except when stopping with a stop signal applied.
2-2* Mechanical Brake
"
For most hoisting applications, it is necessary to
control an electromagnetic brake. To control the
brake, a relay output (relay 01 or relay 02) or a
programmed digital output (terminal 27 or 29) is
required. Normally, this output must be closed
during the time when the drive is unable to "hold"
the motor, e.g. because of too high load.
Select Mechanical Brake Control [32] for applications
with an electromagnetic brake in par. 5-40 (Array
parameter), par. 5-30, or par. 5-31 (digital output
27 or 29). When selecting Mechanical brake control
[32], the mechanical brake is closed during start
until the output current is above the level selected in
par. 2-20 Release Brake Current. During stop, the
mechanical brake activates when the speed is below
the level selected in par. 2-21 Activate Brake Speed
[RPM]. If the adjustable frequency drive enters into
an alarm condition or an overcurrent or overvoltage
situation, the mechanical brake immediately cuts
in. This is also the case during safe stop.
2-20 Release Brake Current
Range:
0.00 - par. 4-51 A
* default setting ( )
How to Program
[1]
[2]
*
display text [ ] value for use in communication via serial communication port
MG.33.B3.22 - VLT is a registered Danfoss trademark
Function:
Set the motor current for release of the mechanical
brake, if a start condition is present.
2-21 Activate Brake Speed [RPM]
Range:
0 - par. 4-53 RPM
Function:
Set the motor speed for activating the mechanical
brake, if a stop condition is present.
2-22 Activate Brake Speed [Hz]
Range:
0 - Max. speed
Function:
Set the motor frequency for activating the
mechanical brake, if a stop condition is present.
2-23 Activate Brake Delay
Range:
0.0 - 5.0 s
Function:
Sets the brake delay time of the coast after
ramp-down time. The shaft is held at zero speed
with full holding torque. Ensure that the mechanical
brake has locked the load before the motor enters
coast mode. See section Mechanical Brake.
0.00A
*
0RPM
*
0Hz
*
0.0s
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