Danfoss VLT AutomationDrive FC 302 Programming Manual page 63

Parameter Descriptions
2-13 Brake Power Monitoring
Option: Function:
[12] Warning & trip
300s
[13] Warning 600s
[14] Trip 600s
[15] Warning & trip
600s
If power monitoring is set to [0] Off or [1] Warning, the
brake function remains active, even if the monitoring limit
is exceeded. This may lead to thermal overload of the
resistor. It is also possible to generate a warning via a
relay/digital outputs. The measuring accuracy of the power
monitoring depends on the accuracy of the resistance of
the resistor (better than ±20%).
2-15 Brake Check
Option: Function:
Parameter 2-15 Brake Check is only active in
frequency converters with an integral dynamic
brake.
Select type of test and monitoring function to
check the connection to the brake resistor, or
whether a brake resistor is present, and then
display a warning or an alarm in the event of a
fault.
NOTICE
The brake resistor disconnection function
is tested during power-up. However, the
brake IGBT test is performed when there is
no braking. A warning or trip disconnects
the brake function.
The testing sequence is as follows:
1. The DC link ripple amplitude is
measured for 300 ms without braking.
2. The DC link ripple amplitude is
measured for 300 ms with the brake
turned on.
3. If the DC link ripple amplitude while
braking is lower than the DC link ripple
amplitude before braking + 1%: Brake
check has failed by returning a warning
or alarm.
4. If the DC link ripple amplitude while
braking is higher than the DC link ripple
amplitude before braking + 1%: Brake
check is OK.
[0] Off Monitors brake resistor and brake IGBT for a
short circuit during operation. If a short circuit
*
occurs, warning 25 appears.
MG33MJ02
Programming Guide
2-15 Brake Check
Option:
[1] Warning
[2] Trip
[3] Stop and
trip
[4] AC brake Monitors for a short circuit or disconnection of
[5] Trip Lock
NOTICE
Remove a warning arising in connection with [0] Off or
[1] Warning by cycling the mains supply. The fault must
be corrected first. For [0] Off or [1] Warning, the
frequency converter keeps running even if a fault is
located.
2-16 AC brake Max. Current
Range:
100 %
*
NOTICE
Parameter 2-16 AC brake Max. Current has no effect when
1-10 Motor Construction [1] PM, non salient SPM.
2-17 Over-voltage Control
Option:
[0] Disabled
*
[1] Enabled (not
at stop)
[2] Enabled
NOTICE
Do not enable OVC in hoisting applications.
Danfoss A/S © Rev. 10/2014 All rights reserved.
Function:
Monitors brake resistor and brake IGBT for a
short circuit and runs a test for brake resistor
disconnection during power-up.
Monitors for a short circuit or disconnection of
the brake resistor, or a short circuit of the brake
IGBT. If a fault occurs, the frequency converter
cuts out while displaying an alarm (trip locked).
Monitors for a short circuit or disconnection of
the brake resistor, or a short circuit of the brake
IGBT. If a fault occurs, the frequency converter
ramps down to coast and then trips. A trip lock
alarm is displayed (e.g. warning 25, 27 or 28).
the brake resistor, or a short circuit of the brake
IGBT. If a fault occurs, the frequency converter
performs a controlled ramp-down. This option is
available for FC 302 only.
Function:
[ 0 - 1000.0 %] Enter the maximum permissible current
when using AC brake to avoid
overheating of motor windings.
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.
No OVC required.
Activates OVC except when using a stop
signal to stop the frequency converter.
Activates OVC.
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