Mitsubishi Electric FR-D700 Series, Instruction Manual

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Setting of acceleration/deceleration time and acceleration/ deceleration pattern
4.7.3 Acceleration/deceleration pattern (Pr. 29)
The above parameters can be set when Pr. 160 Extended function display selection ="0". (Refer to page 157)
You can set the acceleration/deceleration pattern suitable for application.
Parameter
Number
Name Initial Value Setting Range Description
29
Acceleration/deceleration
pattern selection
0
0 Linear acceleration/ deceleration
1 S-pattern acceleration/deceleration A
2 S-pattern acceleration/deceleration B
(1) Linear acceleration/deceleration ( Pr. 29 setting "0", initial value)
For the inverter operation, the output frequency is made to change linearly (linear
acceleration/deceleration) to prevent the motor and inverter from excessive stress
to reach the set frequency during acceleration, deceleration, etc. when frequency
changes. Linear acceleration/deceleration has a uniform frequency/time slope.
(2) S-pattern acceleration/deceleration A (
Pr. 29
= "1")
For machine tool spindle applications, etc.
Used when acceleration/deceleration must be made in a short time to a high-
speed range of not lower than the base frequency.
In this acceleration/deceleration pattern,
Pr. 3 Base frequency (fb) is the inflection
point of the S pattern and you can set the acceleration/deceleration time
appropriate for motor torque reduction in a constant-power operation range of
base frequency (fb) or higher.
NOTE
As the acceleration/deceleration time of S-pattern acceleration/deceleration A, set the time taken until Pr. 3 Base
frequency is reached, not Pr. 20 Acceleration/deceleration reference frequency .
(3) S-pattern acceleration/deceleration B ( Pr. 29 = "2")
For prevention of load shifting in conveyor and other applications.
Since acceleration/deceleration is always made in an S shape from current
frequency (f2) to target frequency (f1), this function eases shock produced at
acceleration/deceleration and is effective for load collapse prevention, etc.
Parameters referred to
Pr. 3 Base frequency Refer to page 80
Pr. 7 Acceleration time, Pr. 8 Deceleration time, Pr. 20 Acceleration/deceleration reference frequency Refer to page 91
(Hz)
Time
Setting value "0"
[Linear acceleration/
deceleration]
Output frequency
fb
(Hz)
Setting value "1"
[S-pattern acceleration/
deceleration A]
Output frequency
Time
f1
(Hz)
(Hz)
f2
Set frequency
Output frequency
Time
Setting value "2"
[S-pattern acceleration/
deceleration B]