Toshiba VF-A7 Trip-less enhancement,  ：PWM carrier frequency, Model Dependent

6.12 PWM carrier frequency

 ：PWM carrier frequency

・Function

1)The sound tone of acoustic noise can be changed by adjusting the PWM carrier frequency. This adjustment is effective in preventing the motor from resonating with its load(machine) or its fan cover.

2)Decreasing the carrier frequency is also effective in reducing electromagnetic.

Note) Decreasing the carrier frequency reduces electromagnetic noise but increases acoustic noise.

[Parameter setting]

Title

Function

Adjustment range

Default setting



PWM carrier frequency

～(, ) [kHz](*1) [Upper limits differ by applicable motor capacity. Refer to the table below.]

Model

dependent

(*1)Setting the PWM carrier frequency larger than the default value, reduction of rated current is needed. For details, refer to figure and table below.

Rated current [%]

	100
	①
		Default setting		②	Upper limit		PWM carrier frequency [kHz]
Voltage	Applicable motor	PWM carrier freq. [kHz]			①Rated current		②Max value, no rated current
class [V]	capacity [kW]	Default setting	Upper limit		at upper limit [%]		reduction is needed [kHz]
	0.4～2.2，	12		15	No need of rated current reduction
	5.5～11，18.5
	3.7	12		15	90		12
	15	12		15	95		12
200	22	12		15	90		12
	30	12		15	93		12
	37	8		15	No need of	rated current reduction
	45	8		15	80		8
	55	2.2		8	85		3
	75，90	2.2		5	No need of	rated current reduction
	0.75～2.2,	12		15	No need of rated current reduction
	5.5～11, 18.5
	3.7，15，22	12		15	90		12
	30	12		15	89		12
400	37	8		15	No need of	rated current reduction
	45	8		15	80		11
	55	8		15	65		8
	75	2.2		8	70		4
	90/110～220	2.2		5	80		2.2
	280	2.2		5	75		2.2

Note1) In vector control mode, set the carrier frequency to 2.2 [kHz] or over. Operation may become unstable if the carrier frequency is lower than 2.2 [kHz].

Note2) In the case that the operation frequency is more than 130Hz,carrier frequency is limited to less than 10kHz automatically.

Note3) Set the carrier frequency to 2.2kHz when sine wave filter (LFL,LFC)is used at output side of inverter. Filter can be damaged by fire in the case of other than 2.2kHz.

6.13 Trip-less enhancement

6.13.1 Auto-restart (restart during free-run (coast))

 ：Auto-restart

 ：Auto-restart adjustment #1

 ：Auto-restart adjustment #2

 ：Auto-restart mode

 ：Auto-restart adjustment #3

Warning

Mandatory

･Do not get near the motor or the machine.

The motor and the machine unexpectedly restart after recovery from a momentary power failure, which might cause injury to persons.

･Stick caution labels to the inverter, the motor and the machine, to prevent accidents due to an unexpected restart of them after recovery from a momentary power failure.

F-20