Hitachi SJ700-2 Disabling the electronic thermal protection, Thermal current 1 2, Current. a

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:

Reduction	Trip time (s)
scale

X1.0

X0.9

X0.8

				Inverter output
0	2.5	5	60	frequency (Hz)

60

3.0

062.8 86.4 115.2

(98.1%)(135%) (180%)

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	b015/b017/
thermal frequency (1) (2)		0. to 400. (Hz)	Setting of frequency at each breakpoint
	b019
(3)
Free setting, electronic	b016/b018/	0.0 (A)	Disabling the electronic thermal protection
		0.1 to rated
thermal current (1) (2) (3)	b020		Setting of the current at each breakpoint
		current. (A)

X1.0

X0.8	Range of
	setting
		Inverter output
0 5	40	frequency (Hz)

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

Trip time (s)

60

3.0

0 (x) (y) (z)

Output current (A)

b020

b018

b016

0b01 b017 b019 A004/A204/A304

Maximum frequency (Hz)

(x): ("setting of b018"/"rated current") x 109%

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

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

(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
Electronic thermal	C061	0.	Disabling the warning output
			Setting of the threshold level to output the
warning level setting		1. to 100. (%) (*1)
			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").

4 - 38