Mitsubishi Electric FR-A820-00046 (0.4K) Instruction Manual page 676

Pr. Name
14
Load pattern selection
G003
 Application for constant-torque load (Pr.14 ="0", initial value)
• The output voltage will change linearly against the output frequency at the base frequency or lower.
• Set this parameter when driving a load that has constant load torque even when the rotation speed is changed, such as
conveyor, dolly, or roll drive.
Select for constant-torque load (setting value "0") even for fan and pump in following cases.
• When accelerating a blower with large moment of inertia (J) in a short period of time.
• When it is a constant-torque load such as rotary pump or gear pump.
• When the load torque increases in low speed such as screw pump.
 Application for variable-torque load (Pr.14 ="1")
• The output voltage will change in square curve against the output frequency at the base frequency or lower. (1.75th-power
curve for the FR-A820-01870(37K) or higher, and the FR-A840-00930(37K) or higher)
• Set this parameter when driving a load with load torque change proportionally against the square of the rotation speed,
such as a fan or pump.
 Vertical lift load applications (Pr.14 = "2, 3")
• Set "2" when a vertical lift load is fixed as power driving load at forward rotation and regenerative load at reverse rotation.
• Pr.0 Torque boost is valid during forward rotation, and torque boost is automatically changed to "0%" during reverse
rotation.
Setting
Initial value
range
0 For constant-torque load
1 For variable-torque load
For constant-torque lift
2
(boost at reverse rotation: 0%)
For constant-torque lift
3
0 (boost at forward rotation: 0%)
RT signal ON...for constant-torque load
4
RT signal OFF...for constant-torque lift, boost at reverse rotation 0%
RT signal ON...for constant-torque load
5
RT signal OFF...for constant-torque lift, boost at forward rotation 0%
12 to 15 Excitation current low-speed scaling factor (Refer to
Pr.14 = 0
100%
Pr. 3 Base frequency
Output frequency (Hz)
Pr.14 = 1
100%
Pr. 3 Base frequency
Output frequency (Hz)
Description
page 677.)
5. PARAMETERS
5.16 (G) Control parameters
1
2
3
4
5
6
7
8
9
10
675