Danfoss VLT AutomationDrive FC 300 Programming Manual page 69

3 Parameter descriptions
2-17 Over-voltage Control
Option:
[0] * Disabled
[1] Enabled (not at stop)
3
[2] Enabled
NB!
OVC must not be enabled in hoisting applications.
2-18 Brake Check Condition
Range:
[0] * At Power Up
[1] After Coast Situations
2-19 Over-voltage Gain
Range:
100 %* [0 - 200 %]
3.4.4 2-2* Mechanical Brake
Parameters for controlling operation of an electro-magnetic (mechanical) brake, typically required in hoisting applications.
To control a mechanical brake, 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, e.g. due to an excessive load. Select
Control
[32] for applications with an electro-magnetic brake in par. 5-40
Digital Output
. When selecting
selected in par. 2-20 Release Brake Current
Brake Speed [RPM] . If the frequency converter enters an alarm condition or an over-current or over-voltage situation, the mechanical brake immediately
cuts in. This is also the case during safe stop.
NB!
Protection mode and trip delay features (par. 14-25
the activation of the mechanical brake in an alarm condition. These features must be disabled in hoisting applications.
68
Function:
Over-voltage control (OVC) reduces the risk of the frequency converter tripping due to an over
voltage on the DC link caused by generative power from the load.
No OVC required.
Activates OVC except when using a stop signal to stop the frequency converter.
Activates OVC.
Function:
Brake check will be performed at power up
Brake check will be performed after coast situations
Function:
Select over-voltage gain.
Mechanical brake control
[32], the mechanical brake is closed from start up until the output current is above the level
. During stop, the mechanical brake activates when the speed falls below the level specified in par. 2-21
MG.33.M8.02 - VLT
Function Relay Terminal 27 Digital Output
, par. 5-30
Trip Delay at Torque Limit
and par. 14-26
®
is a registered Danfoss trademark
FC 300 Programming Guide
Mechanical Brake
Terminal 29
, or par. 5-31
Activate
Trip Delay at Inverter Fault
) may delay