Mechanical Brake; Ac Brake Max. Current; Over-Voltage Control; Brake Check Condition/Over-Voltage Gain - Danfoss VLT AutomationDrive FC 302 Programming Manual

Parameter Descriptions

2-16 AC brake Max. Current

Range: Function:
100 % [ 0 - 1000.0 %] Enter the maximum allowed current
*
when using AC braking to avoid
overheating of motor windings.
NOTICE
Parameter 2-16 AC brake Max. Current has no effect when
parameter 1-10 Motor Construction=[1] PM, non salient
SPM.

2-17 Over-voltage Control

Option: Function:
Overvoltage control (OVC) reduces the risk
of the frequency converter tripping due to
an overvoltage on the DC-link caused by
generative power from the load.
[0] Disabled No OVC required.
*
[1] Enabled (not Activates OVC except when using a stop
at stop) signal to stop the frequency converter.
[2] Enabled Activates OVC.
NOTICE
Do not enable OVC in hoisting applications.
2-18 Brake Check Condition
Range: Function:
[0] At Power Up Brake check is performed at power-
*
up.
[1] After Coast Situations Brake check is performed after coast
situations.
2-19 Over-voltage Gain
Range:
100 % [10 - 200 %]
*
MG33MP02
Programming Guide
Function:
Select overvoltage gain.
Danfoss A/S © 10/2018 All rights reserved.

3.3.3 2-2* Mechanical Brake

Parameters for controlling operation of an electro-magnetic
(mechanical) brake, typically required in hoisting
applications.
To control a mechanical braking, a relay output (relay 01 or
relay 02) or a programmed digital output (terminal 27 or
29) is required. Normally, this output must be closed
during periods when the frequency converter is unable to
hold the motor, for example due to an excessive load.
Select [32] Mechanical Brake Control for applications with
an electro-magnetic brake in parameter 5-40 Function Relay,
parameter 5-30 Terminal 27 Digital Output, or
parameter 5-31 Terminal 29 Digital Output. When selecting
[32] Mechanical brake control, the mechanical braking is
closed from start-up until the output current is above the
level selected in parameter 2-20 Release Brake Current.
During stop, the mechanical braking activates when the
speed drops below the level specified in
parameter 2-21 Activate Brake Speed [RPM]. If the frequency
converter enters an alarm condition, an overcurrent, or
overvoltage situation, the mechanical braking immediately
cuts in. This is also the case during Safe Torque Off.
NOTICE
Protection mode and trip delay features
(parameter 14-25 Trip Delay at Torque Limit and
parameter 14-26 Trip Delay at Inverter Fault) may delay
the activation of the mechanical braking in an alarm
condition. These features must be disabled in hoisting
applications.
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