Mitsubishi Electric FR-A800, Instruction Manual

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(G) Control parameters Parameters
5 - 656
5.16.3 Load pattern selection
Optimal output characteristics (V/F characteristics) for application or load characteristics can be se-
lected.
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. (1.75th-power curve for FR-A820-01870(37K) or higher, and FR-A840-00930(37K) or higher)
●
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.
Parameters referred to
Pr. 14 Load pattern selection => page 5-656
Pr. 29 Acceleration/deceleration pattern selection => page 5-240
Pr. 71 Applied motor => page 5-434
Pr. 83 Rated motor voltage => page 5-67
Pr. 84 Rated motor frequency => page 5-67
Pr. 178 to Pr. 189 (input terminal function selection) => page 5-422
Pr. Name
Initial
value
Setting
range
Description
14
G003
Load pattern selection 0
0 For constant-torque load
1 For variable-torque load
2
For constant-torque lift
(boost at reverse rotation 0%)
3
For constant-torque lift
(boost at forward rotation 0%)
4
RT signal ON.................for constant-torque load
RT signal OFF ...............for constant-torque lift, boost at
reverse rotation 0%
5
RT signal ON.................for constant-torque load
RT signal OFF ...............for constant-torque lift, boost at
forward rotation 0%
Fig. 5-324:
Constant-torque load
I002750E
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.
V/F V/F V/F
100%
Ou
tp
u
t v
o
lt
ag
e
Pr. 3 Base frequency
Output frequency (Hz)