Danfoss FC 300 Programming Manual page 49

Parameter Descriptions
NOTE
Remove a warning arising in connection with Off [0] or
Warning [1] by cycling the mains supply. The fault must
be corrected first. For Off [0] or Warning [1], the frequen-
cy converter keeps running even if a fault is located.
This parameter is only active in frequency converters with an
integral dynamic brake.
2-16 AC brake Max. Current
Range: Function:
100.0 % [Application Enter the maximum permissible
*
dependant] current when using AC brake to avoid
overheating of motor windings. The AC
brake function is available in Flux
mode only (FC 302 only).
2-17 Over-voltage Control
Option: 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.
[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.
NOTE
OVC must not be enabled in hoisting applications.
2-18 Brake Check Condition
Range: Function:
[0] At Power Up Brake check will be performed at
*
power up
[1] After Coast Situations Brake check will be performed after
coast situations
FC 300 Programming Guide
2-19 Over-voltage Gain
Range:
100 %
3.4.3 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 Mechanical Brake Control
[32] for applications with an electro-magnetic brake in
par. 5-40 Function Relay, par. 5-30 Terminal 27 Digital Output, or
par. 5-31 Terminal 29 Digital Output. When selecting Mechani-
cal brake control [32], the mechanical brake is closed from start
up until the output current is above the level selected in
par. 2-20 Release Brake Current. During stop, the mechanical
brake activates when the speed falls below the level specified
in par. 2-21 Activate 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.
NOTE
Protection mode and trip delay features (par. 14-25 Trip
Delay at Torque Limit and par. 14-26 Trip Delay at Inverter
Fault) may delay the activation of the mechanical brake
in an alarm condition. These features must be disabled
in hoisting applications.
®
MG.33.M9.02 - VLT is a registered Danfoss trademark
Function:
[0 - 200 %] Select over-voltage gain.
*
3 3
49