Hitachi SJ700-2 instruction manual Carrier frequency setting, Class

Chapter 4 Explanation of Functions

4.2.35 Carrier frequency setting

The carrier frequency setting function (b083) allows you to change the carrier frequency of the PWM waveform output from the inverter.

Increasing the carrier frequency can lower the metallic noise from the motor, but may increase the inverter noise and current leakage.

You can use this function effectively to avoid resonance of the mechanical system and motor.

Item	Function code	Range of data	Description
Carrier frequency	b083	0.5 to 15.0 (kHz) (*1)
setting

*1 The maximum carrier frequency varies depending on the inverter capacity.

When increasing the carrier frequency (fc), derate the output current as shown in the following table: Derated output current is to be set as electronic thermal protection level (4.2.29).

Derating is not needed when electronic thermal level is already set to lower then derating level.

Voltage		200 V class			400 V class
class
Inverter	Maximum		Derating at fc=15 kHz	Maximum	Derating at fc=15 kHz
capacity	fc (kHz)			fc (kHz)
15kW	12		95% (60.8 A or less)	14	95% (30.4A or less)
18.5kW	10		90% (68.4A or less)	10	90% (34.2A or less)
22kW	7		70% (66.5A or less)	6	75% (36.0A or less)
30kW	5		80% (96.8A or less)	10	75% (43.5A or less)
37kW	10		75% (108.7A or less)	8	80% (60.0A or less)

200 V class									400 V class						37kW	30kW
current	100							15kW	current	100							15kW
	90									90							18.5kW
								18.5kW
	95									95
output	85								output	85				22kW
	80							30kW		80
of	75							37kW	of	75
	70							22kW		70
Derating									Derating
	65									65
	60									60
	55	2	4	6	8	10	12	14 15		55	2	4	6	8	10	12	14 15
	0.5									0.5
			Carrier frequency (kHz)									Carrier frequency (kHz)

If you use the inverter with settings that exceed the rated maximum carrier frequency or derated output current (with a maximum carrier frequency of 15 kHz), the inverter may be damaged or its life may be shortened.

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