Mitsubishi Electric FR-A820-00046 Instruction Manual page 895

Parameters
Pr.
565
G301
566
G302
The setting is applied to the operation under V/F control.
The setting is valid only under Advanced magnetic flux vector control or Real sensorless vector
control. When Pr. 14 = "12 to 15" and V/F control is selected, the operation is the same as the one
for constant-torque load (Pr. 14 = "0").
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.
NOTE 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.
FR-A800
Initial
Name
value
Second motor
excitation current 9999
break point
Second motor
excitation current
9999
low-speed scaling
factor
100%
Pr. 3 Base frequency
Output frequency (Hz)
Setting
Description
range
0 to 400 Hz Set an excitation current break point when the RT signal is ON.
SF-PR/SF-HR/SF-HRCA motor: The predetermined frequency is
applied.
9999
Motor other than the above: 10 Hz is applied.
Set an excitation current low-speed scaling factor when the RT
0 to 300%
signal is ON.
SF-PR/SF-HR/SF-HRCA motor: The predetermined scaling factor is
applied.
9999
Motor other than the above: 130% is applied.
Fig. 5-341:
Constant-torque load
(G) Control parameters
I002750E
5 - 693