# Mitsubishi Electric FR-CS84-012 Instruction Manual Page 95

Freqrol-cs80.

 Acceleration time setting (Pr.7, Pr.20)
• Use
Pr.7 Acceleration time
from stop status.
• Set the acceleration time according to the following formula.
Acceleration time setting =
• For example, the following calculation is performed to find the setting value for
to the maximum frequency of 40 Hz in 10 s with
= 50 Hz × 10 s / (40 Hz - 0.5 Hz) ≈ 12.1 s
Pr.7
Pr.20
(50Hz)
Acceleration
Pr.7
Pr.44
time
 Deceleration time setting (Pr.8, Pr.20)
• Use
Pr.8 Deceleration time
reference frequency
• Set the deceleration time according to the following formula.
Deceleration time setting =
• For example, the following calculation is used to find the setting value for
the maximum frequency of 50 Hz in 10 s with
= 120 Hz × 10 s / (40 Hz - 3 Hz) ≈ 25.5 s
Pr.8
NOTE
• If the acceleration/deceleration time is set, the actual motor acceleration/deceleration time cannot be made shorter than the
shortest acceleration/deceleration time determined by the mechanical system J (moment of inertia) and motor torque.
• If the Pr.20 setting is changed, the Pr.125 and Pr.126 (frequency setting signal gain frequency) settings do not change.
Set Pr.125 and Pr.126 to adjust the gains.
 Setting multiple acceleration/deceleration times (RT signal, Pr.44, Pr.45)
are valid when the RT signal is ON.
Pr.44 and Pr.45
• When "9999" is set in
NOTE
• The reference frequency during acceleration/deceleration depends on the setting of Pr.29 Acceleration/deceleration
pattern. (Refer to
• The RT signal can be assigned to an input terminal by setting Pr.178 to Pr.182 (Input terminal function selection). Changing
the terminal assignment may affect other functions. Set parameters after confirming the function of each terminal.
• Set "3" in any of Pr.178 to Pr.182 (Input terminal function selection) to assign the RT signal to another terminal.
94
5. PARAMETERS
5.4 (F) Setting of acceleration/deceleration time and acceleration/deceleration pattern
to set the acceleration time required to reach
× Acceleration time from stop status to maximum frequency / (maximum frequency -
Pr.20
Running
frequency
Time
Deceleration
Pr.8
Pr.45
time
to set the deceleration time required to reach stop status from
.
× deceleration time from maximum frequency to stop / (maximum frequency -
Pr.20
, the deceleration time becomes equal to the acceleration time (
Pr.45
page
95.)
Pr.20 Acceleration/deceleration reference frequency
= 50 Hz (initial value) and
Pr.20
= 120 Hz and
= 3 Hz.
Pr.20
Pr.10
when increasing the output frequency
Pr.7
= 0.5 Hz.
Pr.13
Pr.20 Acceleration/deceleration
when decreasing the output frequency from
Pr.8
).
Pr.44
)
Pr.13
)
Pr.10