Adv. Mech Brake; Torque Ref; Torque Ramp Up Time; Gain Boost Factor - Danfoss VLT AutomationDrive FC 302 Programming Manual

Parameter Descriptions
Motor
Speed
3 3
Torque
Ref.
Brake
Relay
High
Low
Mech Brake
Feedback
High
Low
Open
Mech Brake
Position
Closed
Gain Boost or
Postion Control
Illustration 3.20 Brake Release Sequence for Hoist Mechanical Brake Control
Parameter 2-26 Torque Ref to parameter 2-33 Speed PID Start
Lowpass Filter Time are only available for the hoist
mechanical brake control (flux with motor feedback).

2-26 Torque Ref

Range:
0 % [ -300 -
300 %]
*

2-27 Torque Ramp Up Time

Range:
0.2 s [0 - 5 s] The value defines the duration of the torque
*
74
Torque Ramp Brake Release
Up Time Time
p. 2-27 p. 2-25
Torque Ref. p. 2-26
W22
Active
Contact no.1
E.g. DI32 [70] Mech. Brake Feedback
Contact no.2
OPTIONAL
E.g. DI33 [71] Mech. Brake Feedback
Gain Boost. p. 2-28
Function:
The value defines the torque applied against the
closed mechanical brake before release.
The torque/load on a crane is positive and is 10–
160%. To obtain the best starting point, set
parameter 2-26 Torque Ref to approximately 70%.
The torque/load on a lift can be both positive
and negative and between -160% and +160%. To
obtain the best starting point, set
parameter 2-26 Torque Ref to 0%.
The higher the torque error is
(parameter 2-26 Torque Ref vs. actual torque), the
more movement during load takeover.
Function:
ramp in clockwise direction. Value 0 enables
very fast magnetization in flux control principle.
Danfoss A/S © 10/2018 All rights reserved.
®
VLT AutomationDrive FC 301/302
Ramp 1 Up
P. 3-41
A22
Active

2-28 Gain Boost Factor

Range:
1 [0 -
*
4 ]
2-29 Torque Ramp Down Time
Range:
0 s
*

3.3.5 2-3* Adv. Mech Brake

Parameter 2-30 Position P Start Proportional Gain to
parameter 2-33 Speed PID Start Lowpass Filter Time can be
set up for very smooth transition change from speed
control to position control during parameter 2-25 Brake
Release Time - the time when the load is transferred from
the mechanical brake to the frequency converter.
Parameter 2-30 Position P Start Proportional Gain to
parameter 2-33 Speed PID Start Lowpass Filter Time are
activated when parameter 2-28 Gain Boost Factor is set to 0.
See Illustration 3.20 for more information.
Ramp 1 Down Stop Delay Activate Brake
P. 3-42 P. 2-24 Delay
P. 2-23
A22
Active
Function:
Only active in flux closed loop. The function ensures
a smooth transition from torque control mode to
speed control mode when the motor takes over the
load from the brake.
Increase to minimize the movement. Activate the
advanced mechanical braking (parameter group 2-3*
Adv. Mech Brake) by setting parameter 2-28 Gain
Boost Factor to 0.
Function:
[0 - 5 s] Torque ramp-down time.
Torque Ramp
Down Time
p. 2-29
W22
Active
MG33MP02