GE C11 Electrical measurements in the Main Circuit, Three-phase, Single -phase, Output motor side

Models: C11 AF-300

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8-3 Electrical measurements in the Main Circuit

8-3 Electrical measurements in the Main Circuit

The indicated values depend on the meter types because of harmonic components included in the voltage and current of the main power supply (input) and the output (motor) side of the drive. Therefore, when measuring with a meter for the commercial power frequency, use the meters shown in Table 8-3-1.

The power-factor cannot be measured using the power-factor meter available on the market which measures the phase difference between voltage and current. When the power-factor must be measured, measure the power, voltage, and current on the input side and output side. Then, calc ulate the power-factor using the following formu- las:

Three-phase

Power factor =

Electric power [W]

x 100 [%]

3 x Voltage [V] x Current [A]

 

 

Single -phase

 

 

Power factor =

Electric power [W]

x 100 [%]

 

Voltage [V] x Current [A]

Table 8-3-1 Meter for measuring the main circuit

Item

Input (power supply) side

 

 

Output (motor) side

 

 

DC circuit

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Current

 

 

 

 

 

 

 

 

 

 

Voltage

 

 

 

 

 

Voltage

 

Current

 

 

 

 

 

waveform

 

waveform

 

 

 

waveform

 

waveform

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Terminal section

Meter name

Meter type

Symbol

Ammeter

Moving- iron type

Voltmeter

Rectifier or moving-iron type

Wattmeter

Power me- ter

-

Ammeter

Moving- iron type

Voltmeter

Rectifier type (*1)

Wattmeter

Power me- ter

-

DC voltme- ter

V

Moving-coil

type

(*1) When measuring the output voltage by rectifier type meter, an error may occur. Use a digital AC power meter for good accuracy.

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GE C11 Electrical measurements in the Main Circuit, Three-phase, Single -phase, 3-1 Meter for measuring the main circuit