Limiting The Rotation Speed; Maximum/Minimum Setting (Pr. 1, Pr. 2) - Mitsubishi Electric FR-D720-0.2K-G Instruction Manual

4.6

Limiting the rotation speed

Purpose
Set upper limit and lower limit of
rotation speed
Perform operation by avoiding
mechanical resonance points
4.6.1

Maximum/minimum setting (Pr. 1, Pr. 2)

Motor speed can be limited.
Clamp the upper and lower limits of the rotation speed.
Parameter
Name
Number
1 Maximum setting
2 Minimum setting

The value left of the slash is for the 2.2K drive unit or lower. The one right of the slash is for the 3.7K drive unit.

If a value exceeding the upper speed limit of the motor is set, the actual operation will be limited at the maximum rotation speed. The setting range is for the
S-PM motor. The maximum setting value differs depending on the number of poles of the applied motor.
Rotation speed
(r/min)
Pr. 1
Pr. 2
0
(4mA)
Clamped at the
minimum setting
REMARKS
 Because the speed is limited by the speed command, the upper limit value or a higher value may be displayed on the monitor.
(2) Set minimum speed
 Use Pr. 2 Minimum setting to set the minimum rotation speed.
 If the set speed is less than Pr. 2, the rotation speed is clamped at Pr. 2 (will not fall below Pr. 2 ).
REMARKS

When Pr. 15 Jog speed setting is equal to or less than Pr. 2, the Pr. 15 setting has precedence over the Pr. 2 setting.

When stall prevention is activated to decrease the rotation speed, the rotation speed may drop to Pr. 2 or below.

Because the speed is limited by the speed command, the lower limit value or a lower value may be displayed on the monitor.
Note that when Pr. 2 is set to any value equal to or more than Pr. 13 Starting speed, simply turning ON the start
signal will run the motor at the preset speed according to the set acceleration time even if the command speed
is not input.
Parameters referred to
Pr. 13 Starting speed
Pr. 15 Jog speed setting
Pr. 125 Terminal 2 speed setting gain speed, Pr. 126 Terminal 4 speed setting gain speed
Parameter that should be Set
Maximum/minimum
setting
Speed jump
Initial Value
3000r/min
0r/min
(1)
 Use Pr. 1 Maximum setting to set the maximum rotation speed. If the
Clamped at the
maximum setting
value of the speed command entered is higher than the setting, the
rotation speed is clamped at the maximum speed.
 The speed command is also clamped at the operable speed range
of the selected motor.
If the motor's operable maximum speed < maximum setting, the
Speed setting
speed does not increase to the maximum speed.
5, 10V
(20mA)
CAUTION
Refer to page 99.
Refer to page 91.

Limiting the rotation speed

Pr. 1, Pr. 2
Pr. 31 to Pr. 36
Setting Range
0 to 12000r/min /
Upper limit of the output speed.
0 to 8000r/min 
0 to 3600r/min /
Lower limit of the output speed.
0 to 2400r/min 
Set maximum speed
Refer to page 152.
Refer to Page
87
88
Description
87
4