Mitsubishi Electric FR-A700 Technical Manual page 205

2) S-pattern acceleration/deceleration B [Pr. 29 = 2]
common
S-pattern acceleration/deceleration
accelerating/decelerating in S-pattern when
frequency is changed (running frequency by
external input signal or operation panel). Therefore
reducing an impact during start or stop, and effective
for load collapse prevention. For example, when set
frequency changes as the following diagram, S-
pattern is active. (Example: conveyor)
f
2
f
1
S-pattern acceleration/deceleration B
3) S-pattern acceleration/deceleration C [Pr. 29 = 4, Pr.
380 to 383]
A700
Assign S-pattern
switching signal (X20) to an input terminal, and use
S-pattern acceleration/deceleration C switching
signal (X20) to switch the acceleration/ deceleration
curve.
Change the S-pattern acceleration/deceleration C
switch (X20 signal) after the speed becomes
constant. S-pattern operation before switching
continues even if the X20 signal is changed during
acceleration or deceleration.
Frequency
[Pr.382]
Output frequency Output frequency Output frequency
Set frequency Set frequency Set frequency
[Pr.380]
S-pattern
acceleration/
OFF
deceleration
C switchover
(X20)
X20 Signal During acceleration
[Pr. 380 Acceleration S-
OFF
pattern 1]
[Pr. 382 Acceleration S-
ON
pattern 2]
Set % of time taken for forming an S-pattern in [Pr.
380, 383] as acceleration/deceleration time is
100%.
Parameter setting (%) Ts/T
S-pattern
acceleration
Ts
T
B is for
set
Time
acceleration/deceleration C
[Pr.381]
[Pr.383]
Time
OFF
ON
During
deceleration
[Pr. 381 Deceleration S-
pattern 1]
[Pr. 383 Deceleration S-
pattern 2]
100%
Linear acceleration
Ts
4) S-pattern acceleration/deceleration D [Pr. 29 = 5,
Pr. 516 to 519]
Set the time taken for S-pattern operation of S-
pattern acceleration/deceleration using [Pr. 516 to
519].
[Pr.516] [Pr.517]
Output Output Output
frequency frequency frequency
Start signal Start signal Start signal
Even if the start signal is turned OFF during
acceleration, the inverter will not decelerate
immediately to avoid sudden frequency change.
(Likewise, the inverter will not immediately
accelerate when deceleration is changed to
reacceleration by turning the start signal ON
during deceleration, etc.)
When S-pattern acceleration/deceleration D is
set, acceleration/deceleration time will become
longer as follows:
The set acceleration/deceleration
indicates the time taken for actual linear
acceleration/deceleration calculated based on [Pr.
7, 8, 44, 45, 110 or 111].
Actual acceleration time T2 = set acceleration time T1+
(S-pattern time at a start of acceleration + S-pattern time at a
completion of acceleration)/2
Actual deceleration time T2 = set deceleration time T1+
(S-pattern time at a start of deceleration + S-pattern time at a
completion of deceleration)/2
[Example] When starting the inverter with an S-pattern
acceleration/deceleration D selected from a stop to
60Hz in the parameter initial setting as shown below
[Pr.516]
Linear acceleration
[Pr.516] /2
slope of [Pr.7]
T1
T2
Set acceleration
= (Set frequency - [Pr. 13])
time T1
[Pr. 7] / [Pr. 20]
= (60Hz - 0.5Hz) 5s/60Hz
4.96s (actual acceleration time
at linear acceleration)
Set acceleration
= set acceleration time T1 +
time T2
([Pr. 516] + [Pr. 517])/2
= 4.96s + (0.1s + 0.1s)/2
= 5.06s(acceleration time at S-pattern
acceleration)
239
PARAMETER
A700
[Pr.518] [Pr.519]
ON ON ON
time
[Pr.517]
Set frequency Set frequency Set frequency
[Pr.517] /2
Starting frequency [Pr.13]
Time
T1
2