Mitsubishi Electric FR-A820-00046 (0.4K), Instruction Manual

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(F) Setting of acceleration/deceleration time and acceleration/deceleration pattern Parameters
5 - 252
I001553E
Fig. 5-96: Characteristic for parameter 29 = 5
NOTE Even if the start signal is turned OFF during acceleration, the inverter will not decelerate immedi-
ately to avoid sudden frequency change. (Likewise, the inverter will not immediately accelerate
when deceleration is changed to re-acceleration by turning the start signal ON during decelera-
tion, etc.)
Example The following table shows the actual acceleration time when starting the inverter by selecting S-
pattern acceleration/deceleration D from a stop to 60 Hz, as shown below, with the initial parame-
ter settings.
I001554E
Fig. 5-97: Actual acceleration time when starting
Set acceleration time T1 = (Set frequency – Pr. 13) × Pr. 7 / Pr. 20
= (60 Hz - 0.5 Hz) × 5 s / 60 Hz
= 4.96 s (actual acceleration time at linear acceleration)
Actual acceleration time T2 = Set acceleration time T1 + (Pr. 516 + Pr. 517) / 2
= 4.96 s + (0.1 s + 0.1 s) / 2
= 5.06 s (acceleration time at S-pattern acceleration)
Time
Pr. 516
ON
Pr. 517 Pr. 518 Pr. 519
Start signal
Out
p
ut
fr
eque
nc
y
Starting frequency
(Pr. 13)
Pr. 516
T1
Pr. 517
Pr. 517/2
Pr. 516/2
T2
Linear acceleration
Slope of Pr. 7, Pr. 44, Pr. 110
Acceleration/deceleration reference
frequency (Pr. 20)