Danfoss VLT Midi Drive FC 280 Programming Manual page 44

Parameter Descriptions
2-12 Brake Power Limit (kW)
Range:
4 4
2-14 Brake voltage reduce
Range:
0 V [ 0 - 70 V] Setting this parameter may change the brake
*
2-16 AC Brake, Max current
Range:
100 % [0 -
*
160 %]
2-17 Over-voltage Control
Option:
[0] Disabled
*
[1] Enabled
(not at
stop)
[2] Enabled
42
VLT
Function:
P is the average power dissipated in
br,avg
the brake resistor. R is the resistance of
br
the brake resistor. t is the active breaking
br
time within the 120 s period T
U is the DC voltage where the brake
br
resistor is active. For T4 units, the DC
voltage is 770 V, which can be reduced by
parameter 2-14 Brake voltage reduce.
NOTICE
If R is not known or if T
br br
from 120 s, the practical approach is
to run the brake application, read out
parameter 16-33 Brake Energy Average,
and then enter this value + 20% in
parameter 2-12 Brake Power Limit
(kW).
Function:
resistor (parameter 2-11 Brake Resistor (ohm)).
Function:
Enter the maximum allowed current when
using AC brake to avoid overheating of
motor windings.
NOTICE
Parameter 2-16 AC Brake, Max current
is not available for all PM motors, for
example, all of the PM options in
parameter 1-10 Motor Construction.
Function:
Overvoltage control (OVC) reduces the risk of
the frequency converter tripping due to an
overvoltage on the DC link caused by
generative power from the load.
No OVC required.
Activate OVC except when using a stop signal
to stop the frequency converter.
Activate OVC.
Danfoss A/S © 07/2016 All rights reserved.
®
Midi Drive FC 280
2-17 Over-voltage Control
Option:
.
br
2-19 Over-voltage Gain
is different
Range:
100 %
*
2-20 Release Brake Current
Range:
0 A [0 - 100
*
A]
2-22 Activate Brake Speed [Hz]
Range:
0 Hz [0 - 400 Hz] Set the motor frequency for activation of
*
2-23 Activate Brake Delay
Range:
0 s [0 - 5 s] Enter the brake delay time of the coast after
*
Function:
WARNING
PERSONAL INJURY AND EQUIPMENT
DAMAGE
Enabling OVC in hoisting applications
may lead to personal injuries and
equipment damage. Do not enable OVC
in such applications.
Function:
[0 - 200 %] Select overvoltage gain.
Function:
Set the motor current for release of the
mechanical brake when a start condition is
present. The upper limit is specified in
parameter 16-37 Inv. Max. Current.
NOTICE
When mechanical brake control output is
selected, but no mechanical brake is
connected, the function does not work by
default setting due to too low motor
current.
Function:
the mechanical brake when a stop
condition is present.
Function:
ramp-down time. The shaft is held at 0 speed
with full holding torque. Ensure that the
mechanical brake has locked the load before the
motor enters coast mode.
MG07C302