Hioki 9605-01, Instruction Manual, Page: 95 / 100

APPENDIX 9
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NOTE
NOTE
Rotation-sensor signal
(Magnetic-pole position signal)
Phase difference
Fundamental wave
component of the
induced voltage
θ
The 3194 can be used for the following measurement when a rotation-sensor
signal (e.g., magnetic-pole position signal) is input.
(1) Zero-correction of phase difference
The 3194 is capable of zero-correction of the phase difference (electrical
angle) between the rotation-sensor signal and the induced voltage
fundamental wave. If this correction is made, line voltages generated when
the motor is driven by an inverter, and the line current vectors can be
evaluated by evaluating the rotation-sensor signals instead. Accurate
correction will be made even if the induced voltage is distorted, as the 3194
extracts the fundamental wave from the induced voltage using its harmonic
analysis function.
To ensure reproducibility, the motor must have the same rotational pulse
count as when the 3194 is used with a dividing setting of 1/1. For example,
the pulse count must be 2 pulses/rotation in the case of a 4-pole motor.
(2) Harmonic measurement of induced voltage
The 3194 is capable of harmonic measurement of the induced voltage. Using
the harmonic analysis function, the 3194 measures the rms value,
fundamental wave component, and harmonic of the induced voltage (line
voltage). In addition, using the
Δ - Y conversion function, the induced
voltage may be converted to a phase voltage.
・ For the phase difference ( θ ), the absolute accuracy is not specified. The
accuracy will be specified as a deviation, based on a comparison of one
cycle of induced voltage with one cycle of the rotation-sensor signal. In
addition, the 3194 measures the distance between the rising edge of the
rotation-sensor signal and the rising zero-crossing of the induced-voltage
fundamental wave.
・ The zero-correction setting is valid for a single piece of data only. If the
frequency changes, zero-correction must be performed again.
・
The zero-correction setting is cleared when power to the 3194 is turned off.