Mitsubishi Electric 700 Series, Instruction Manual

Page: 103 / 416

92
V/F pattern
4.5.3 Adjustable 5 points V/F (Pr. 71, Pr. 100 to Pr. 109)
The above parameters can be set when Pr. 160 User group read selection = "0". (Refer to page 190)
A dedicated V/F pattern is available by freely setting the V/F characteristic between a startup and the base
frequency and base voltage under V/F control (frequency voltage/frequency).
The torque pattern that is optimum for the machine's characteristic can be set.
Parameter
Number
Name Initial Value Setting Range Description
71 Applied motor 0 0, 1, 2, 20
Set "2" for adjustable 5 points V/F
control.
100 V/F1(first frequency) 9999 0 to 400Hz, 9999
Set each points (frequency,
voltage) of V/F pattern.
9999: No V/F setting
101 V/F1(first frequency voltage) 0V 0 to 1000V
102 V/F2(second frequency) 9999 0 to 400Hz, 9999
103 V/F2(second frequency voltage) 0V 0 to 1000V
104 V/F3(third frequency) 9999 0 to 400Hz, 9999
105 V/F3(third frequency voltage) 0V 0 to 1000V
106 V/F4(fourth frequency) 9999 0 to 400Hz, 9999
107 V/F4(fourth frequency voltage) 0V 0 to 1000V
108 V/F5(fifth frequency) 9999 0 to 400Hz, 9999
109 V/F5(fifth frequency voltage) 0V 0 to 1000V
⋅
Any V/F characteristic can be provided by presetting the parameters of
V/F1 (first frequency voltage/first frequency) to V/F5 .
⋅
For a machine of large static friction coefficient and small dynamic
static friction coefficient, for example, set a V/F pattern that will
increase the voltage only in a low-speed range since such a machine
requires large torque at a start.
(Setting procedure)
1)Set the rated motor current in Pr. 19 Base frequency voltage . (No
function at the setting of "9999" (initial value) or "8888".)
2)Set Pr. 71 Applied motor to "2" (Adjustable 5 points V/F
characteristic).
3)Set the frequency and voltage you want to set in Pr. 100 to Pr. 109 .
CAUTION
⋅
Adjustable 5 points V/F characteristics function only under V/F control or Optimum excitation control. They do not function for
Simple magnetic flux vector control.
⋅
When Pr. 19 Base frequency voltage = "8888" or "9999", Pr. 71 cannot be set to "2". To set Pr. 71 to "2", set the rated voltage value in Pr. 19 .
⋅
When the frequency values at each point are the same, a write disable error ( ) appears.
⋅
Set the points (frequencies, voltages) of Pr. 100 to Pr. 109 within the ranges of Pr. 3 Base frequency and Pr. 19 Base frequency voltage .
⋅
When "2" is set in
Pr. 71
,
Pr. 47 Second V/F (base frequency)
will not function.
⋅
When Pr. 71 is set to "2", the electronic thermal relay function makes calculation as a standard motor.
REMARKS
⋅
A greater energy saving effect can be expected by combining Pr. 60 Energy saving control selection and adjustable 5 points V/F.
⋅
For the FR-F720-00250 and 00340 and the FR-F740-00126 and 00170, the Pr.0 Torque boost and Pr.12 DC injection brake
operation voltage settings are automatically changed according to the Pr. 71 setting.
♦
Parameters referred to
♦
⋅
Pr. 3 Base frequency, Pr. 19 Base frequency voltage Refer to page 89
⋅
Pr. 12 DC injection brake operation voltage Refer to page 112
⋅
Pr. 47 Second V/F (base frequency) Refer to page 89
⋅
Pr. 60 Energy saving control selection Refer to page 163
⋅
Pr. 71 Applied motor Refer to page 111
⋅
Pr. 80 Motor capacity, Pr. 90 Motor constant (R1) Refer to page 79
Base frequency
voltage
Pr.19
Base frequency
Pr.3
Torque boost
Pr.0
V/F Characteristic
0
V/F5
V/F4
V/F3
V/F2
V/F1
Frequency
Voltage
CAUTION
Make sure to set this parameter correctly according to the motor used.
Incorrect setting may cause the motor to overheat and burn.
Pr. 71
Standard Motor Setting
0, 2, 20
Constant-torque Motor Setting
1
Pr. 0 3% 2%
Pr. 12 4% 2%