Siemens SINAMICS V20 Operating Instructions Manual page 261

Parameter Function
P1200 Flying start
Starts converter onto a rotating motor by rapidly changing the output frequency of the converter until the
actual motor speed has been found. Then, the motor runs up to setpoint using the normal ramp time.
0
1
2
3
4
5
6
Notice: Flying start must be used in cases where the motor may still be turning (e.g. after a short mains break) or
can be driven by the load. Otherwise, overcurrent trips will occur.
Note: Useful for motors with high inertia loads. Settings 1 to 3 search in both directions. Settings 4 to 6 search
only in direction of setpoint.
P1202[0...2] Motor-current: flying start
[%]
Defines search current used for flying start. Value is in [%] based on rated motor current (P0305).
Note: Reducing the search current may improve performance for flying start if the inertia of the system is not
very high. However, search current settings in P1202 that are below 30% (and sometimes other settings
in P1202 and P1203) may cause motor speed to be found prematurely or too late, which can result in F1
or F2 trips.
P1203[0...2] Search rate: flying start
[%]
Sets factor (in V/f mode only) by which the output frequency changes during flying start to synchronize
with turning motor. This value is entered in [%]. It defines the reciprocal initial gradient in the search se-
quence. P1203 influences the time taken to search for the motor frequency.
Example: For a motor with 50 Hz, 1350 rpm, 100 % would produce a maximum search time of 600 ms.
Note: A higher value produces a flatter gradient and thus a longer search time. A lower value has the opposite
effect.
r1204 Status word: flying start
V/f
Bit parameter for checking and monitoring states during search.
Bit
00
01
02
03
04
05
07
SINAMICS V20 Converter
Operating Instructions, 10/2019, A5E34559884-012
Range
0 - 6
Flying start disabled
Flying start always active; searches in both directions
Flying start active after power on, fault, OFF2; searches in both directions
Flying start active after fault, OFF2; searches in both directions
Flying start always active; searches in direction of setpoint only
Flying start active after power on, fault, OFF2; searches in direction of setpoint
only
Flying start active after fault, OFF2; searches in direction of setpoint only
10 - 200
10 - 500
-
Signal name
Current applied
Current could not be applied
Voltage reduced
Slope-filter started
Current less threshold
Current-minimum
Speed could not be found
Factory Can be
default changed
0 U, T
100 U, T
100 U, T
- -
Parameter list
8.2 Parameter list
Scaling Data Data
set type
- - U16
- DDS U16
- DDS U16
- - U16
1 signal 0 signal
Yes No
Yes No
Yes No
Yes No
Yes No
Yes No
Yes No
Acc.
Level
2
3
3
4
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