Danfoss VLT AutomationDrive FC 300 Instruction Manual page 56

4 How to Program
NOTE!
Digital input should be set to [0]
2-10 Brake Function
Option:
[0] * Off
[1] Resistor brake
4
[2] AC brake
2-11 Brake Resistor (ohm)
Range:
Application [Application dependant]
dependent*
2-12 Brake Power Limit (kW)
Range:
Application [Application dependant]
dependent*
For 200–240 V units:
For 380–480 V units
For 380–500 V units
For 575–600 V units
This parameter is only active in adjustable frequency drives with an integral dynamic brake.
4-10
PNP - Active at 24V
in par. 5-00.
Function:
No brake resistor is installed.
A brake resistor is incorporated in the system, for dissipating surplus brake energy as heat. Con-
necting 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.
Is selected to improve braking without using a brake resistor. This parameter controls an overmag-
netization 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.
Function:
Set the brake resistor value in Ohms. This value is used for monitoring the power to the brake
Brake Power Monitoring
resistor in par. 2-13
drives with an integral dynamic brake.
Use this parameter for values without decimals. For a selection with two decimals, use
par. 30-81 Brake Resistor (ohm)
Function:
Set the monitoring limit of the braking energy transmitted to the resistor.
The monitoring limit is a product of the maximum duty cycle (120 sec.) and the maximum power
of the brake resistor at that duty cycle. See the formula below.
390 2 ×
dutytime
P resistor
=
[W]
R
× 120
778 2 ×
dutytime
P resistor
=
[W]
R
× 120
810 2 ×
dutytime
P resistor
=
[W]
R × 120
2
dutytime
943 ×
P resistor =
[W]
R × 120
MG.33.AG.22 - VLT
VLT ® AutomationDrive FC 300 Instruction
. This parameter is only active in adjustable frequency
.
®
is a registered Danfoss trademark
Manual