505 START FUNCTION (2.4.6)
Table 152: Selections for parameter ID505
Selection
number
Selection name
Description
0
Ramp
The AC drive starts from 0 Hz and accelerates to the set ref-
erence frequency within the set acceleration time. (Load
inertia or starting friction may cause prolonged acceleration
times).
1
Flying start
The AC drive is able to start into a running motor by applying
small current pulses to motor and searching for the fre-
quency corresponding to the speed the motor is running at.
Searching starts from the maximum frequency towards the
actual frequency until the correct value is detected. There-
after, the output frequency will be increased/ decreased to
the set reference value according to the set acceleration/
deceleration parameters.
Use this mode if the motor is coasting when the start com-
mand is given. With the flying start it is possible to start the
motor from actual speed without forcing the speed to zero
before ramping to reference.
2
Conditional flying start
With this mode it is possible to disconnect and connect the
motor from the AC drive even when the Start command is
active. On re-connecting the motor, the drive will operate as
described in selection 1.
PARAMETER DESCRIPTIONS
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