Atec Yokogawa-WT3000 - Manual (Page 7)

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• Simultaneous Measurement of Voltage, Current, and THD
(Total Harmonic distortion)
Testing of lighting devices often involves measurement of voltage, current, and THD,
a parameter that indicates the quality of power. This is because distortion in voltage
and current waveforms is becoming more prevalent due to the increasing complexity
of control systems.
The WT3000 can simultaneously measure voltage and current with THD, eliminating
these inconveniences and allowing for more accurate and rapid measurements of an
instrument’s characteristics and fluctuations.
˾ Lamp Current Measurement
Since lamp current flows inside of fluorescent tubes, normally it cannot be measured
directly. However, lamp current can be displayed by measuring secondary current
and cathode current and finding the difference in their instantaneous values using
the delta computation function (/DT option).
• Related applications
Evaluation of power quality in equipment designed to be connected in a system,
such as UPSs and power conditioners
Evaluation of Lighting Devices
You can measure power consumption in mobile phones, batteries, and other
equipment powered by dry cells. You can perform a variety of operation tests for
reducing power consumption by using the current or power integration function. This
offers a powerful means of evaluating instruments, such as for checking control
modes for lengthening battery life.
Major Features
• 5mA range for very low current measurements
• Checking power consumption integration of mobile phones when switching modes
(using integration functions)
• Visually observing trends in power consumption using trend display functions that
allow checking of temporal fluctuations
• Checking the waveform of the consumed current
• Null function can be used to subtract the DC offset
Use the 2A input element for small current consumption.
Measurement of Power Consumption in Mobile Phones
• High Accuracy Even at Low Power Factors
The WT3000 represents great improvement over previous models in terms of power
factor error (it is approximately three times more accurate). With improved
measurement accuracy in the lower power factors—such as with transformers, active
power values can be measured with higher precision.
• Simultaneous Measurement of RMS and MEAN of Voltage
Voltage RMS (the true RMS value) and voltage MEAN (rectified mean value
calibrated to the rms value) can be measured at the same time, allowing for
measurement of corrected power (Pc).
• Phase Voltage Confirmation
The delta computation function (/DT option) allows both star-delta and delta-star
conversion.
High Accuracy Measurements of Transformers
• Conversion Efficiency Measurement
Renewable energy source of photovoltaic power generation and wind power is
converted dc to ac using power conditioner. The WT3000 Precision Power Analyzer
provides measurement with world-class DC and AC signal accuracies.
Measuring Conversion Efficiency of Power Conditioner
• Basic power accuracy of ± 0.02% of
reading
The WT3000 can be used as a reference
instrument for periodic in-house calibration of
general-purpose power measurement
instruments, such as the WT300 series.
Reference equipment for power calibration
Temperature- and humidity-controlled
calibration room
Example of integration graph display Current consumption in mobile phones
Measure the DC voltage, DC current,
and power conversion efficiency Since images can be saved, they can be pasted
as-is into reports as evaluation and test data.
* THD stands for total harmonic distortion. In other words, the distortion factor.
* Please be aware that during lighting testing, the measured values and efficiencies may not be
stable since the power conversion efficiency fluctuates over time due to the emission of heat.
Solar cell module
Example of Overview of a Photovoltaic Power Conditioner
booster
converter
DC/AC
converter
Load
Power Link
A
V
Ballast
A A
V V
Flourescent
lamp
Secondary current Cathode current