Danfoss VLT AutomationDrive FC 300 Series Programming Manual page 132

Parameter Descriptions
14-10 Mains Failure
Option: Function:
[5] Kinetic The difference between kinetic back-up with and
back-up, without trip is that the latter will always ramp
trip down to 0 RPM and trip, regardless of whether
mains return or not.
The function is made so that it will not even
detect if mains return, this is the reason for the
relatively high level on the DC-link during ramp
down.
U [V]
DC
790 V
U DC
14-11*1.35
n [RPM]
Ref
0
Illustration 3.55
A = Normal Operation
B = Mains failure
Table 3.24
[6] Alarm
[7] Kin. Kinetic back-up with recovery combines the
back-up, features of kinetic back-up and kinetic back-up
trip w with trip. This feature makes it possible to select
recovery between kinetic back-up and kinetic back-up with
trip, based on a recovery speed, configurable in
14-15 Kin. Backup Trip Recovery Level. In order to
make it possible to detect if mains return. If mains
do not return, the frequency converter ramps
down to 0 RPM and trips. If mains return while in
kinetic back-up at a speed above the value in
14-15 Kin. Backup Trip Recovery Level, normal
operation is resumed. This is equal to [4] Kinetic
Back-up. The DC-level during [7] Kinetic back-up is
par. 14-11 * 1,35.
U DC [V]
U DC
14-11*1.35
n [RPM]
Ref
14-15
Illustration 3.56 [7] Kinetic Back-Up, trip with
recovery where mains return above 14-15 Kin.
Backup Trip Recovery Level.
®
VLT AutomationDrive Programmming Guide
A B C D
t [S]
t [S]
C = Kinetic back-up
D = Trip
A B C D A E
t [S]
t [S]
®
MG33ME02 - VLT is a registered Danfoss trademark
14-10 Mains Failure
Option: Function:
A = Normal Operation D = Mains return
B = Mains failure
C Kinetic back-up
Table 3.25
If mains return while in kinetic back-up at a speed
below 14-15 Kin. Backup Trip Recovery Level the
frequency converter ramps down to 0 RPM using
the ramp and then trips. If the ramp is slower
than the system will ramp down on its own, the
ramping will be done motoric and U
the normal level (U
A
U DC [V]
U DC
14-11*1.35
n [RPM]
Ref
0
Illustration 3.57 [7] Kinetic Back-Up, trip with
recovery, trip slow ramp where mains return
below 14-15 Kin. Backup Trip Recovery Level. In
this illustration a slow ramp is used.
A = Normal Operation D = Mains return
B = Mains failure
C Kinetic back-up
Table 3.26
If the ramp is quicker than the system will ramp
down on its own, the ramping will be done
generatoric. This results in a higher U
limited using the brake chopper/ resistor brake.
A
U DC [V]
U DC
U DC
14-11*1.35
n [RPM]
Ref
0
Illustration 3.58 [7] Kinetic Back-Up, trip with
recovery where mains return below 14-15 Kin.
Backup Trip Recovery Level. In this illustration a
quick ramp is used.
E = Normal operation:
ramping
will be at
DC
*1.35).
DC, m
B C D E F
t [S]
t [S]
E = Kinetic back-up,
ramping to trip
F = Trip
which is
DC
B C D E F
t [s]
t [s]
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