Mitsubishi Electric 800 Series Instruction Manual (Function page 236

 Changing the minimum increment of the acceleration/deceleration time
(Pr.21)
• Use Pr.21 to set the minimum increment of the acceleration/deceleration time.
Setting value "0" (initial value): minimum increment 0.1 s
Setting value "1": minimum increment 0.01 s
• Pr.21 setting allows the minimum increment of the following parameters to be changed.
Pr.7, Pr.8, Pr.16, Pr.44, Pr.45, Pr.791, Pr.792, Pr.1103
NOTE
• Pr.21 setting does not affect the minimum increment setting of Pr.611 Acceleration time at a restart.
• The operation panel provides a 4-digit readout (including the number of decimal places) on a value of parameters. Therefore,
a value of "100" or larger is set/displayed only in increments of 0.1 second even if Pr.21 = "1".
• When Pr.21 is set to "0" after the time is set in 0.01 s increments while Pr.21 is set to "1", the value is displayed in increments
of 0.1 second (rounded down to one decimal place). However, the value for the acceleration/deceleration time setting can be
set in increments of 0.01 second.
 Setting multiple acceleration/deceleration times (RT signal, Pr.44, Pr.45,
and Pr.147)
• Pr.44 and Pr.45 are applied when the RT signal is ON or when the output frequency is equal to or higher than the
frequency set in Pr.147 Acceleration/deceleration time switching frequency.
• Even at the frequency lower than the Pr.147 setting, turning ON the RT signal switches the acceleration/deceleration time
to the second acceleration/deceleration time. The priority of the signals and settings is as follows: RT signal > Pr.147
setting.
• When "9999" is set in Pr.45, the deceleration time becomes equal to the acceleration time (Pr.44).
• While the Pr.147 setting is equal to or less than the setting of Pr.10 DC injection brake operation frequency or the Pr.13
Starting frequency, the time used as the acceleration/deceleration time switches to the time set in Pr.44 (Pr.45) when the
output frequency reaches or exceeds the Pr.10 or Pr.13 setting.
Pr.147 setting
9999 (initial value)
0.00 Hz
0.01 Hz ≤ Pr.147 ≤ Set frequency
Set frequency < Pr.147
Output frequency
(Hz)
Set
frequency
Pr. 147
setting
Pr.7 Pr.44
RT signal
NOTE
• The reference frequency during acceleration/deceleration depends on the Pr.29 Acceleration/deceleration pattern
selection setting. (Refer to
• The RT signal can be assigned to an input terminal by setting Pr.178 to Pr.189 (Input terminal function selection). Changing
the terminal assignment may affect other functions. Set parameters after confirming the function of each terminal.
• The RT signal is the Second function selection signal which also enables other second functions. (Refer to
Acceleration/deceleration time
Pr.7, Pr.8
Pr.44, Pr.45
Output frequency < Pr.147: Pr.7, Pr.8
Pr.147 ≤ Output frequency: Pr.44, Pr.45
Pr.7, Pr.8
Pr.44 Pr.8
(Pr.45)
ON
page 238.)
Description
Acceleration/deceleration time is not
automatically changed.
Second acceleration/deceleration time is
applied from the start.
Acceleration/deceleration time is
automatically changed.
Not changed as the frequency has not
reached the switchover frequency.
Pr.44
Pr.44
Pr.7
(Pr.45)
10. (F) Settings for Acceleration/Deceleration
10.1 Setting the acceleration and deceleration time
1
2
3
4
5
6
7
8
9
10
Time
Pr.8
page 374.)
235