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2-05 Maximum Reference
Range:
Function:
unit matches the option selected in
parameter 1-00 Configuration Mode
and the unit in
parameter 3-01 Reference/Feedback
Unit
.
2-06 Parking Current
Range:
Function:
50 %
*
[ 0 -
1000 %]
Set current as percentage of rated motor
current,
. Is
used when enabled in
2-07 Parking Time
Range:
Function:
3 s
*
[0.1 - 60 s] Set the duration of the parking current set in
parameter 2-06 Parking Current
, once activated.
3.3.2 2-1* Brake Energy Funct.
Parameter group for selecting dynamic brake parameters.
Only valid for frequency converters 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
dissipation of 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
frequency converters with an integral dynamic
brake.
[2] AC brake Improves 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.
NOTICE
The AC brake is not as efficient as dynamic
braking with resistor.
AC brake is for VVC
+
mode in both open
and closed loop.
2-11 Brake Resistor (ohm)
Range:
Function:
Size
related
*
[ 0 -
65535
Ohm]
Set the brake resistor value in
Ω
. This value
is used for monitoring the power to the
brake resistor in
2-11 Brake Resistor (ohm)
Range:
Function:
. This parameter is only active in
frequency converters with an integral
dynamic brake.
Use this parameter for values without
decimals. For a selection with 2 decimals,
use
parameter 30-81 Brake Resistor (ohm)
.
2-12 Brake Power Limit (kW)
Range:
Function:
Size
related
*
[ 0.001 -
2000.000
kW]
Parameter 2-12 Brake Power Limit (kW)
is
the expected average power dissipated in
the brake resistor over a period of 120 s.
It is used as the monitoring limit for
parameter 16-33 Brake Energy Average
and
thereby specifies when a warning/alarm is
to be given.
To calculate
, the following formula can be
used.
P
br, avg
W =
U
br
2
V × t
br
s
R
br
Ω × T
br
s
P
br,avg
is the average power dissipated in
the brake resistor, R
br
is the resistance of
the brake resistor. t
br
is the active
breaking time within the 120 s period,
T
br
.
U
br
is the DC voltage where the brake
resistor is active. This depends on the
unit as follows:
T2 units: 390 V
T4 units: 810 V
T5 units: 810 V
T6 units: 943 V/1099 V for D – F frames
T7 units: 1099 V
NOTICE
If R
br
is not known, or if T
br
is
different from 120 s, the practical
approach is to run the brake
application, read
parameter 16-33 Brake Energy
Average
and then enter this
+ 20% in
.
2-13 Brake Power Monitoring
Option:
Function:
This parameter is only active in frequency
converters with a brake.
This parameter enables monitoring of the
power to the brake resistor. The power is
calculated based on the resistance
Parameter Descriptions
Programming Guide
MG33MP02
Danfoss A/S © 10/2018 All rights reserved.
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Содержание VLT AutomationDrive FC 302
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