Danfoss VLT AutomationDrive Programming Manual Download

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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

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]

3.4.2 2-1* Brake Energy Funct.

Parameter 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

plus

and flux mode in both

open-loop and closed-loop.

2-11 Brake Resistor (ohm)

Range:

Function:

Size related

[ 5.00 - 65535.00 Ohm]

2-12 Brake Power Limit (kW)

Range:

Function:

Size related