Hitachi SJ300 Series Measurements, General Inverter, Notes, Note 1:, Note 2:, Note 3:, Parameter, Measuring, instrument, of measurement, Reference Value, Circuit location

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SJ300 Inverter

General Inverter The following table specifies how to measure key system electrical parameters. The diagrams

Electrical on the next page show inverter-motor systems and the location of measurement points for these Measurements parameters.

Parameter	Circuit location	Measuring	Notes	Reference Value
	of measurement	instrument
Supply voltage	ER – across L1 and L2	Moving-coil type	Fundamental	Commercial supply
E1	ES – across L2 and L3	voltmeter or recti-	wave effective	voltage (200V class)
	ET – across L3 and L1	fier type voltmeter	value	200-240V, 50/60 Hz
				400V class 380-
				460V, 50/60 Hz
Supply current	Ir – L1, Is – L2, It – L3	Moving-coil type	Total effective	—
I1		ammeter	value
Supply power W1	W11 – across L1 and L2	Electronic type	Total effective	—
	W12 – across L2 and L3	wattmeter	value
Supply power	W1			—
factor Pf1
	Pf1 = ----------------------------- ⋅ 100%
	3 ⋅ E1	⋅ I1
Output voltage	EU – across U and V	Rectifier type	Total effective	—
E0	EV – across V and W	voltmeter	value
	EW – across W and U
Output current Io	IU – U	Moving-coil type	Total effective	—
	IV – V	ammeter	value
	IW – W
Output power Wo	W01 – across U and V	Electronic type	Total effective	—
	W02 – across V and W	wattmeter	value
Output power	Calculate the output power factor from the output voltage E, output			—
factor Pfo	current I, and output power W.
		W0
	Pf0 = ----------------------------- ⋅ 100%
	3	⋅ E0 ⋅ I0

Note 1: Use a meter indicating a fundamental wave effective value for voltage, and meters indicating total effective values for current and power.

Note 2: The inverter output has a distorted waveform, and harmonic frequencies may cause erroneous readings. However, the measuring instruments and methods listed above provide reasonably accurate results.

Note 3: A general-purpose digital volt meter (DVM) is not usually suitable to measure a distorted waveform (not pure sinusoid).

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