Danfoss FC 300 Series, Programming Manual

Page: 49 / 216

3.4 Parameters: 2-** Brakes
3.4.1 2-0* DC Brakes
Parameter group for configuring the DC brake and DC hold
functions.
2-00 DC Hold Current
Range: Function:
50
%
*
[Application
dependant]
Enter a value for holding current as a
percentage of the rated motor current I
M,N
set in 1-24 Motor Current . 100% DC holding
current corresponds to I
M,N
.
This parameter holds the motor function
(holding torque) or pre-heats the motor.
This parameter is active if DC hold is
selected in 1-72 Start Function [0] or
1-80 Function at Stop [1].
NOTE!
The maximum value depends on the rated motor current.
Avoid 100% current for too long. It may damage the motor.
Low values of DC hold will produce larger than expected
currents with larger motor power sizes. This error will
increase as the motor power increases.
2-01 DC Brake Current
Range: Function:
50
%
*
[Application
dependant]
Enter a value for current as a percentage of
the rated motor current I
M,N
, see 1-24 Motor
Current . 100% DC braking current
corresponds to I
M,N
.
DC brake current is applied on a stop
command, when the speed is lower than
the limit set in 2-03 DC Brake Cut-in Speed
[RPM] ; when the DC Brake Inverse function
is active; or via the serial communication
port. The braking current is active during
the time period set in 2-02 DC Braking
Time .
NOTE!
The maximum value depends on the rated motor current.
Avoid 100% current for too long. It may damage the motor.
2-02 DC Braking Time
Range: Function:
10.0 s
*
[0.0 - 60.0 s] Set the duration of the DC braking current
set in 2-01 DC Brake Current , once activated.
2-03 DC Brake Cut-in Speed [RPM]
Range: Function:
Application
dependent
*
[Application
dependant]
Set the DC brake cut-in
speed for activation of the
DC braking current set in
2-01 DC Brake Current , upon
a stop command.
2-04 DC Brake Cut-in Speed [Hz]
Range: Function:
Application
dependent
*
[Application
dependant]
Set the DC brake cut-in
speed for activation of the
DC braking current set in
2-01 DC Brake Current , upon
a stop command.
3.4.2 2-1* Brake Energy Funct.
Par. group for selecting dynamic braking parameters. Only
valid for drives with brake chopper.
2-10 Brake Function
Option: Function:
[0]
*
Off No brake resistor is installed.
[1] Resistor
brake
A brake resistor is incorporated in the system, for
dissipating surplus brake energy as heat.
Connecting a brake resistor allows a higher DC
link voltage during braking (generating
operation). The resistor brake function is only
active in adjustable frequency drives with an
integral dynamic brake.
[2] AC brake Is selected to improve braking without using a
brake resistor. This parameter controls an
overmagnetization of the motor when running
with a generatoric load. This function can improve
the OVC function. Increasing the electrical losses
in the motor allows the OVC function to increase
the braking torque without exceeding the
overvoltage limit. Please note that AC brake is not
as effective as dynamic breaking with resistor.
AC brake is for VVC
+
and flux mode in both open-
loop and closed-loop.
Parameter Descriptions FC 300 Programming Guide
MG.33.MA.22 - VLT
®
is a registered Danfoss trademark 3-27
3 3