Mitsubishi Electric 700 Series, Instruction Manual

Page: 102 / 416

91
V/F pattern
4
P
ARA
MET
E
RS
4.5.2 Load pattern selection (Pr. 14)
You can select the optimum output characteristic (V/F characteristic) for the application and load characteristics.
Parameter
Number
Name Initial Value Setting Range Description
14 Load pattern selection 1
0 For constant-torque load
1 For variable-torque loads
The above parameters can be set when Pr. 160 User group read selection = "0". (Refer to page 190)
(1) For constant-torque load (setting "0")
⋅
At or less than the base frequency voltage, the output voltage varies linearly with the
output frequency.
⋅
Set this value when driving the load whose load torque is constant if the speed varies,
e.g. conveyor, cart or roll drive.
(2) For variable-torque load (setting "1", initial value)
⋅
At or less than the base frequency voltage, the output voltage varies with the output
frequency in a square curve.
⋅
Set this value when driving the load whose load torque varies in proportion to the
square of the speed, e.g. fan or pump.
♦
Parameters referred to
♦
Pr. 3 Base frequency Refer to page 89
100%
Output voltage
Pr.3 Base frequency
Output frequency (Hz)
POINT
If the load is a fan or pump, select "For rated torque load (setting "0")" in any of the
following cases.
⋅
When a blower of large moment of inertia (J) is accelerated in a short time
⋅
For constant-torque load such as rotary pump or gear pump
⋅
When load torque increases at low speed, e.g. screw pump
100%
Output voltage
Pr.3 Base frequency
Output frequency (Hz)