Mitsumi electronic FR-F520-0.75K Data examples, Noise Terminal Voltage of Inverter and Example

INSTALLATION AND WIRING

•Data examples

By decreasing the carrier frequency, the noise terminal voltage* can be reduced. Use Pr. 72 to set the carrier frequency to a low value (1kHz). Though motor noise increases at a low carrier frequency, selection of Soft-PWM in Pr. 240 will make it unoffending.

Differences between Noise Terminal Voltages

at Different Carrier Frequencies

Conditions

!Motor: 3.7kW (5HP)

!Average terminal voltage 0dB=1∝ V 120dB=1V

(dB)

120

FR-F520-3.7K

FR-A120E-3.7K fc=14.5kHz

100

voltage

80

fc=0.7kHz

fc=14.5kHz

terminal

60

20

fc=2.0kHz Soft-PWM(Factory setting)

Noise

0.1

0.3

0.5

1

3

5

10

30

0

Noise frequency (MHz)

By decreasing the carrier frequency, noise will be

By using shielded cables as signal cables, induction

about as low as that of our conventional FR-Z200

noise can be reduced greatly (to 1/10 - 1/100).

series.

Induction noise can also be reduced by moving the

signal cables away from the inverter output cables.

(Separation of 30cm (11.81inches) reduces noise to

1/2-1/3.)

By fitting the FR-BSF01 or BLF on the inverter

output side, induction noise to the signal cables can

be reduced.

Noise Terminal Voltage of Inverter and Example

Noise Induced to Signal Cables by Inverter Output

of Its Reduction by Noise Filters

Cables

					Conditions												Conditions
					! Motor:3.7kW (5HP)					100							! Inverter: FR-F520-3.7K
					! Average terminal voltage			0dB=1∝ V	(dB)								! Motor: SF-JR 4P 3.7kW (5HP)
								120dB=1V		80			Parallel cable				! Output frequency: 30Hz
terminal voltage (dB)	120								Induction voltage								! Noise form: Normal mode
					FR-Z220-3.7K
													Twisted pair cable
	100									60								5cm
																	Inverter	d(cm) Motor
	80									40
													Coaxial cable
	60																FR-BLF
																		Terminal
										20						FR-BSF01
	20				FR-F520-3.7K(fc=0.7kHz)												(4T) Measuring instrument
Noise											0						Line-to-line distance, d (cm)
	0											10	20	30	40	50
	0.1	0.3	0.5	1	3	5	10	30

Noise frequency (MHz)

*Noise terminal voltage: Represents the magnitude of noise propagated from the inverter to the power supply.

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