[2] Trip Trips frequency converter and displays an alarm when the calculated power exceeds 100% of the
monitoring limit.
[3] Warning and trip Activates both of the above, including warning, trip and alarm.
If power monitoring is set to
Off
[0] or
Warning
[1], 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:
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.
NB!
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 discon-
nects 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.
[1] Warning Monitors brake resistor and brake IGBT for a short-circuit, and runs a test for brake resistor dis-
connection during power-up.
[2] Trip 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).
[3] Stop and trip 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).
[4] AC brake 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 performs a controlled ramp-down. This option is
available for FC 302 only.
[5] Trip Lock
NB!
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 frequency 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 dependant] Enter the maximum permissible current when using AC brake to avoid overheating of motor wind-
ings. The AC brake function is available in Flux mode only (FC 302 only).
FC 300 Programming Guide 3 Parameter descriptions
MG.33.M8.02 - VLT
®
is a registered Danfoss trademark
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