Danfoss VLT HVAC Drive FC 102 Programming Manual page 57

Parameter Descriptions
2-07 Parking Time
Range: Function:
3 s [0.1 - 60 Set the duration of the parking current time set
*
s] in parameter 2-06 Parking Current. Active in
connection with parameter 1-73 Flying Start.
NOTICE
Parameter 2-07 Parking Time is only active
when [1] PM, non-salient SPM is selected
in 1-10 Motor Construction.
3.4.2 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:
Available selections depend on
parameter 1-10 Motor Construction:
[0] Asynchron:
[0] Off
[1] Resistor brake
[2] AC brake
[1] PM non-salient:
[0] Off
[1] Resistor brake
[0] Off No brake resistor installed.
[1] Resistor Brake resistor incorporated in the system, for
brake 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 AC brake only works in compressor torque mode
in parameter 1-03 Torque Characteristics.
2-11 Brake Resistor (ohm)
Range: Function:
Set the brake resistor value in Ω. This
Size [ 5.00 -
related 65535.00
value is used for monitoring the power
*
Ohm]
to the brake resistor in
parameter 2-13 Brake Power Monitoring.
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 30-81 Brake Resistor (ohm).
MG11CE02
Programming Guide
2-12 Brake Power Limit (kW)
Range:
Size
related
*
Danfoss A/S © 03/2015 All rights reserved.
Function:
[ 0.001 - Parameter 2-12 Brake Power Limit (kW) is
2000.000 the expected average power dissipated in
kW] the brake resistor over a period of 120 s.
It is used as the monitoring limit for
16-33 Brake Energy Average and thereby
specifies when a warning/alarm is to be
given.
To calculate parameter 2-12 Brake Power
Limit (kW), the following formula can be
used.
2
U V × t s
br br
P W =
br, avg
R Ω × T s
br br
P is the average power dissipated in
br,avg
the brake resistor, R
the brake resistor. t
br
breaking time within the 120 s period,
T .
br
U is the DC voltage where the brake
br
resistor is active. This depends on the
unit as follows:
T2 units: 390 V
T4 units: 778 V
T5 units: 810 V
T6 units: 943 V/1099 V for D – F frames
T7 units: 1099 V
NOTICE
If R is not known, or if T
br
different from 120 s, the practical
approach is to run the brake
application, readout 16-33 Brake
Energy Average and then enter this
+ 20% in 2-12 Brake Power Limit
(kW).
3
is the resistance of
br
is the active
is
br
55
3