Shortest Acceleration/Deceleration (Automatic Acceleration/Deceleration) (Pr. 61 To Pr. 63, Pr. 292, Pr. 293) - Mitsubishi Electric FR-E720-600 Instruction Manual

Setting of acceleration/deceleration time and acceleration/ deceleration pattern
4.8.4 Shortest acceleration/deceleration (automatic acceleration/deceleration)
(Pr. 61 to Pr. 63, Pr. 292, Pr. 293)
The inverter operates in the same conditions as when appropriate values are set in each parameter even if
acceleration/deceleration time and V/F pattern are not set. This function is useful when you just want to operate, etc.
without fine parameter setting.
Parameter
Name
Number
61 Reference current
Reference value at
62
acceleration
Reference value at
63
deceleration
Automatic acceleration/
292
deceleration
Acceleration/deceleration
293 individual operation
selection
(1) Shortest acceleration/deceleration mode (Pr. 292 = "1, 11", Pr. 293)
Set when you want to accelerate/decelerate the motor for the shortest time. It is desired to make acceleration/deceleration
in a shorter time for a machine tool etc. but the design values of machine constants are unknown.
Acceleration/deceleration speed is automatically adjusted at a start of acceleration/deceleration from the value of the
setting value of Pr. 7 Acceleration time and Pr. 8 Deceleration time so that acceleration/deceleration is made with the
maximum torque the inverter can output. (The setting values of Pr. 7 and Pr. 8 are not changed.)
Either acceleration or deceleration can be made in the shortest time using Pr. 293 Acceleration/deceleration separate selection
mode. When the setting value is "0" (initial value), both acceleration and deceleration can be made in the shortest time.
Set "11" when an optional MRS, MYS type brake resistor, high-duty brake resistor or brake unit is connected. Deceleration
time can be further shortened.
When the shortest/acceleration mode is selected, the stall prevention operation level during acceleration/deceleration from
the value of becomes 150% (adjustable using Pr. 61 to Pr. 63 ). Setting of Pr. 22 Stall prevention operation level is used only
during a constant speed operation.
It is inappropriate to use for the following applications.
a) Machine with a large inertia such as a fan (more than 10 times). Since stall prevention operation will be activated for
a long time, this type of machine may be brought to an alarm stop due to motor overloading, etc.
b) It is desired to always perform operation with a constant acceleration/deceleration time.
c) It is desired to perform operation making sure the inverter and motor have enough capability.
REMARKS
Even if automatic acceleration/deceleration mode has been selected, inputting the jog signal (jog operation) or RT signal
(second function selection) during an inverter stop will switch to the normal operation and give priority to jog operation or
second function selection. Note that JOG and RT signal input is invalid even if JOG signal and RT signal are input during
operation in automatic acceleration/deceleration mode.
Since acceleration/deceleration is made with the stall prevention operation being activated, the acceleration/deceleration speed
always varies according to the load conditions.
Note that when proper values are set in Pr. 7 and Pr. 8, acceleration/deceleration time may be shorter than selecting shortest
acceleration/deceleration mode.
Initial Setting
Value Range
Set the reference current during shortest
0 to 500A
9999 acceleration/deceleration.
9999 Rated inverter output current value is reference
0 to 200% Set the limit value during shortest acceleration.
9999
9999 150% is a limit value
0 to 200% Set the limit value during shortest deceleration.
9999
9999 150% is a limit value
0 Normal mode
1 Shortest acceleration/deceleration (without brake)
0
11 Shortest acceleration/deceleration (with brake)
Brake sequence mode 1, 2
7, 8
(Refer to page 127)
Both acceleration and deceleration are made in the
0
shortest acceleration/deceleration mode
Only acceleration is made in the shortest
0 1
acceleration/deceleration mode
Only deceleration is made in the shortest
2
acceleration/deceleration mode
Description
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