Mitsubishi Electric FR-A820-00046 Instruction Manual page 454

(F) Setting of acceleration/deceleration time and acceleration/deceleration pattern
Fig. 5-96:
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.
Fig. 5-97:
Set acceleration time T1
Actual acceleration time T2 = Set acceleration time T1 + (Pr. 516 + Pr. 517) / 2
5 - 252
Pr. 516 Pr. 517
Start signal
Characteristic for parameter 29 = 5
Pr. 516
Pr. 516/2
T1
T2
Actual acceleration time when starting
= (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)
= 4.96 s + (0.1 s + 0.1 s) / 2
= 5.06 s (acceleration time at S-pattern acceleration)
Pr. 518
ON
Pr. 517
Acceleration/deceleration reference
frequency (Pr. 20)
Pr. 517/2
Linear acceleration
Slope of Pr. 7, Pr. 44, Pr. 110
Starting frequency
(Pr. 13)
Parameters
Pr. 519
Time
I001553E
I001554E