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. 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 300ms without braking.
2.
The DC link ripple amplitude is
measured for 300ms with the brake
turned on.
3.
If the DC link ripple amplitude while
braking is lower than the DC link ripple
amplitude before b 1 %. Brake
check failed, return a warning or alarm.
4.
If the DC link ripple amplitude while
braking is higher than the DC link
ripple amplitude before b 1 %.
Brake check OK.
[0]
*
Off
Monitors brake resistor and brake IGBT for a
short-circuit during operation. If a short-circuit
occurs, a warning appears.
[1]
Warning
Monitors brake resistor and brake IGBT for a
short-circuit, and to run a test for brake resistor
disconnection 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.
[4]
AC brake
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 frequency
converter keeps running even if a fault is located.
2-16 AC brake Max. Current
Range:
Function:
100.0 %
*
[0.0 - 1000.0
%]
Enter the maximum permissible
current when using AC brake to avoid
overheating of motor windings. The
AC brake function is available in Flux
mode only ( only).
NOTE
will not have effect when
= [1] PM, non salient SPM.
2-17 Over-voltage Control
Option:
Function:
[0]
Disabled
No OVC required.
[2]
*
Enabled
Activates OVC.
NOTE
will not have effect when
= [1] PM, non salient SPM.
NOTE
The ramp time is automatically adjusted to avoid tripping
of the frequency converter.
Parameter Description
VLT
®
HVAC Drive Programming Guide
MG.11.CC.02 - VLT
®
is a registered Danfoss trademark
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