Hitachi L700 SERIES Instruction Manual page 100

Chapter 4 Explanation of Functions
(a) Reduced-torque characteristic
The time-limit characteristic determined by the value of "b012", "b212", or "b312" is integrated with each
frequency multiplied by reduction scales.
Reduction
scale
X1.0
X0.8
X0.6
0
5 16
0 6 20
(b) Constant-torque characteristic
Make this setting when driving a constant-torque motor with the inverter.
Reduction
scale
X1.0
X0.9
X0.8
0 2.5 5
(c) Free setting of electronic thermal characteristic
To protect the motor against overheating, you can set the electronic thermal characteristic freely according
to the load on the motor.
The range of setting is shown in the figures below.
Item
Free setting, electronic
thermal frequency (1) (2)
(3)
Free setting, electronic
thermal current (1) (2) (3)
Inverter output
frequency (Hz)
50
60
Base frequency
(Example) Setting on the L700-185LFF (rated current: 73A)
When "b012" is 73 A, and output frequency is 2.5 Hz:
Inverter output
frequency (Hz)
60
Function code
b015/b017/
b019
b016/b018/
b020
Example) Setting on the L700-185LFF (rated current: 73 A)
When "b012" is 64 A, the base frequency is 60 Hz,
and output frequency is 20 Hz:
Trip time (s)
60
0.5
0
(87.2%)
Trip time (s)
60
0.5
0
71.6
(98.1%)
Range of data
0. to 400. (Hz) Setting of frequency at each breakpoint
0.0 (A) Disabling the electronic thermal protection
0.1 to rated
Setting of the current at each breakpoint
current. (A)
4 - 38
Trip time (s)
Motor current (A)
(Ratio to the rated
current of inverter)
Motor current (A)
63.7 70.1 87.6
(Ratio to the rated
(120%) (160%)
current of inverter)
Motor current (A)
78.8 98.6
(Ratio to the rated
(108%) (135%)
current of inverter)
Description