Mitsubishi Electric 800 Series Instruction Manual page 169

 Setting the acceleration/deceleration time in the low-speed range (Pr.791,
Pr.792)
• If torque is required in the low-speed range (less than 10% of the rated motor frequency) under PM sensorless vector
control, set the Pr.791 Acceleration time in the low-speed range and Pr.792 Deceleration time in low-speed range
settings higher than the Pr.7 Acceleration time and Pr.8 Deceleration time settings so that the mild acceleration/
deceleration is performed in the low-speed range. (When the RT signal is turned ON, the second acceleration/deceleration
time is prioritized.)
Acceleration time
in low-speed range
Slope set by Pr. 791
NOTE
• Set Pr.791 (Pr.792) to a value larger than the Pr.7 (Pr.8) setting. If set as Pr.791 < Pr.7, the operation is performed as Pr.791
= Pr.7. If set as Pr.792 < Pr.8, the operation is performed as Pr.792 = Pr.8.
 Emergency stop function (Pr.1103)
• When the Emergency stop (X92) signal is ON, the deceleration stop is performed according to the settings in the Pr.1103
Deceleration time at emergency stop and Pr.815 Torque limit level 2.
• To input the X92 signal, set "92" in any parameter from Pr.178 to Pr.189 (Input terminal function selection) to assign
the function to a terminal.
• The X92 signal is a normally closed input (NC contact input) when it is input via an external input terminal, and a normally
open input (NO contact input) when it is input via communication.
• "PS" is displayed on the operation panel during activation of the emergency stop function.
Output frequency
Start signal
X92
ON
NOTE
• The X92 signals 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.
Parameters referred to
Pr.3 Base frequencypage 386
Pr.10 DC injection brake operation
Pr.29 Acceleration/deceleration pattern
Pr.125, Pr.126 (frequency setting gain
Pr.178 to Pr.189 (Input terminal function
168
8. (F) Settings for Acceleration/Deceleration
8.1 Setting the acceleration and deceleration time
Acceleration time Deceleration time
Slope set by Pr.7 Slope set by Pr.8
Deceleration
by an emergency stop
Normal
acceleration
Time
ON OFF ON
OFF ON
frequencypage 392
selectionpage 169
frequency)page 282
selection)page 292
Low-speed range
(rated motor frequency/10)
Time
Deceleration time
in low-speed range
Slope set by Pr.792