Description of parameters
vacon • 35
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500
Acceleration/Deceleration
ramp
1 shape
(2.4.1)
The start and end of acceleration and deceleration ramps can be smoothed with these
parameters. Setting value 0 gives a linear ramp shape which causes acceleration and
deceleration to act immediately to the changes in the reference signal.
Setting a value 0.1…10 seconds for this parameter produces an S-shaped acceleration/
deceleration. The acceleration time is determined with parameters
Figure 13. Acceleration/Deceleration (S-shaped)
504
Brake
chopper
(2.4.2)
0 = No brake chopper used
1 = Brake chopper in use and tested when running. Can be tested also in READY state
2 = External brake chopper (no testing)
3 = Used and tested in READY state and when running
When the frequency converter is decelerating the motor, the inertia of the motor and the load
are fed into an external brake resistor. This enables the frequency converter to decelerate the
load with a torque equal to that of acceleration (provided that the correct brake resistor has
been selected). See separate Brake resistor installation manual.
505
Start
function
(2.1.11)
Ramp:
0
The frequency converter starts from 0 Hz and accelerates to the set reference
frequency within the set
. (Load inertia or starting friction may
cause prolonged acceleration times).
Flying start:
1
The frequency converter is able to start into a running motor by applying a small
torque to motor and searching for the frequency 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. Thereafter, 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 command is given. With the
flying start it is possible to ride through short mains voltage interruptions.
ID103, ID104
[Hz]
[t]
ID500
ID500
NX12K20
