Chapter 4 explanation of functions – Hitachi SJ700-2 User Manual

Page 101

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Chapter 4 Explanation of Functions

(b) Constant-torque characteristic
Make this setting when driving a constant-torque motor with the inverter.

(Example) Setting on the SJ700-150LF (rated current: 64 A)
When "b012" is 64 A, and output frequency is 2.5 Hz:

X1.0

0

60

X0.9

X0.8

5

2.5

Reduction
scale

Inverter output
frequency (Hz)

62.8

(98.1%)

86.4

(135%)

115.2

(180%)

60

3.0

0

Trip time (s)

Motor current (A)
(Ratio to the rated
current of inverter)










(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

Function code

Range of data

Description

Free setting, electronic
thermal frequency (1) (2)
(3)

b015/b017/

b019

0. to 400. (Hz)

Setting of frequency at each breakpoint

0.0 (A)

Disabling the electronic thermal protection

Free setting, electronic
thermal current (1) (2) (3)

b016/b018/

b020

0.1 to rated
current. (A)

Setting of the current at each breakpoint

Output

A004/A204/A304

b020

b018

b016

b01

b017

b019

0

X1.0

5

40

X0.8

0

60

3.0

(x) (y)

(z)

0

Inverter output
frequency (Hz)

Range of
setting

(Example) When the output frequency is equal
to the setting of "b017"

(x): ("setting of b018"/"rated current") x 109%
(y): ("setting of b018"/"rated current") x 150%
(z): ("setting of b018"/"rated current") x 200%

Maximum frequency (Hz)

Trip time (s)

current (A)


















(3) Thermal warning
You can configure this function so that the inverter outputs a warning signal before the electronic thermal
protection operates against motor overheat. You can also set the threshold level to output a warning signal
with the electronic thermal warning level setting (C061).
To output the warning signal, assign function "13" (THM) to one of the intelligent output terminals [11] to
[15] (C021 to C025) and the alarm relay terminal (C026).

Item Function

code

Data

Description

0.

Disabling the warning output

Electronic thermal
warning level setting

C061

1. to 100. (%) (*1)

Setting of the threshold level to output the
thermal warning signal

*1 Set the ratio (%) of the warning level to the integrated value of the electronic thermal characteristic. A

setting of 100% corresponds to the inverter trip due to overload (error code "E05").

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