Precision Power Scope – High-accuracy time-based power measurement

Precision power measurement gives true insights into energy consumption and performance.

DL850E ScopeCorders— Watch the PX8000 Video —


  • Simultaneous power calculation:
    Provides simultaneous voltage and current multiplication to give real-time power sampling.
  • Cycle-by-cycle power trend measurement:
    Trend measurements between waveforms can be calculated by mathematical functions (up to 4 million points).
  • Supports the capture of power waveforms over specific periods of time
  • X-Y display and phase analysis:
    Supports X-Y axis displays as standard as well as, lissajous waveforms of input and output for phase analysis.
  • Capturing sudden or irregular phenomena:
    A always-active History function automatically records up to 1,000 historical waveforms
  • Long-period data capture and analysis
  • FFT analysis
  • Detailed transient analysis
||||| [+] Features Cont’d
  • Simultaneous harmonic measurement:
    Simultaneously measure the harmonic components of voltage and current waves as well as the harmonic distortion factor.
  • Multifunction snapshots:
    Up to 16 different waveforms- inluding voltage, current and power, can be displayed side-by-side, giving engineers instant snapshots of performance.
  • Trend calculation:
    Built-in functions for the direct calculation of variables, such as root mean square (RMS) and mean power values, to enable the identification of cycle-by-cycle trends.
  • De-skew compensation:
    Automatic de-skewing funtion eliminates offsets between current and voltage signals that may be caused by sensor or input characteristics.


  • Vector Bar Graph Display
  • Built-in Printer
  • Probe Power Output
  • Time Sync Signal Input
  • Harmonic analysis function


  • Precision power measurement of energy consumption and the integration of electronics into power-based systems
  • Sustainable power
  • Inverter and motor testing
  • Reactor loss measurement of inverter boost circuits
  • Transient responses of industrial robots
  • Wireless charger efficiency measurement, and voltage and power measurements in electricity distribution systems


Traditional power measurement instruments cannot provide accurate time measurements; oscilloscopes are not designed to measure power. The PX8000 is the world’s first precision power scope, bringing oscilloscope-style time-based measurement to the world of power measurement. It can capture voltage and current waveforms precisely, opening up applications and solutions for a huge variety of emerging power measurement problems.

IIII [+] Read More

The new instrument has 12-bit resolution with 100 MS/s sampling and 20MHz bandwidth. This means that the PX8000 can be used for accurate measurement of inverter pulse shapes, which can then be used to fine-tune inverter efficiency. A choice of input modules covers voltage, current and sensor measurements at voltages up to 1000 V RMS and currents up to 5 A RMS, with a basic accuracy of ±0.1%. Higher currents can be measured with external current sensors. The PX8000 can be configured to evaluate single phase and three-phase electrical systems.

The PX8000 is powered by Yokogawa’s isoPRO™ technology, which offers industry-leading isolation performance at the highest speeds. isoPRO core technology, designed with energy-saving applications in mind, delivers the performance needed to evaluate high-efficiency inverters that operate at high voltages, large currents and high frequency.

The instrument also supports the capture of power waveforms over specific periods of time and cycle-by-cycle trends through the definition of start and stop “cursors”. This is particularly useful for examining transient phenomena and in the design of periodically controlled equipment. To ensure that such equipment complies with energy standards, it is vital to measure power consumption across a range of different modes from “sleep” to full activity – and all the transient states in between.

A variety of functions including arithmetical calculations, time shifting and Fast Fourier Transforms enables users to display waveforms with offsets and skew corrections. An automatic de-skewing function eliminates offsets between current and voltage signals that may be caused by sensor or input characteristics. Users can also define their own computations via equations that combine differentials, integrals, digital filters and a wealth of other functions.

The PX8000 makes it possible to simultaneously measure the harmonic components of voltage and current waveforms as well as the harmonic distortion factor. Harmonic measurements take place in parallel with conventional voltage and current measurements. Harmonics up to the 500th order of the fundamental can be measured.

  • Literature
  • Specifications
Literature and Technical Information
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Test & Measurement

++ PX8000 Precision Power Scope Brochure (6.2 MB)
Model: Yokogawa PX8000 Precision Power Scope
Models PX8000
Input : Plug in input module style
Number of module slots 8
Module structure Voltage module, Current module and Auxiliary (AUX) module
Power measurement element: one Voltage module and one Current module
Max 8 modules (max 4 power measurement elements) can be installed
AUX module can be installed max 3 (at least one power measurement elements should be installed)
Max. record length: Standard 10 M points for each voltage and current regardless installed module number
The memory cannot combined, each memory of module is individual.
50 M points for voltage and current regardless of the installed channel number of module when/M1 option is installed
100 M points for voltage and current regardless of the installed channel number of module when/M2 option is installed
Enhanced trigger
Trigger source: Un, In, Pn, AUXn or EXT
Trigger type: A → B(N): A Delay B: Edge on A: AND: OR: B>Time: B<Time: B Time Out: B Between: Period: T>Time T<Time: T1<T<T2: T<T1, T<T2: Wave Window
Time Base
Time axis setting (Observation time) "Time/div": Time/div setting: 100 ns/div to 1 s/div (1-2-5 step), 2 s/div, 3 s/div, 4 s/div, 5 s/div, 6 s/div, 8 s/div, 10 s/div, 20 s/div, 30 s/div, 1 min/div and 2 min/div Observation time: 1us to 1200 s
Display: 10.4 inch TFT LCD display
Available displaying size: 210.4 mm × 157.8 mm
Number of dots: Number of dots
Waveform displaying dot size: 801 × 656 (Waveform Display)
Displaying format: Combination:
Max 2 types of format can be displayed
Numeric 4 items/ 8 items/ 16 items/Matrix/All/Single List/Dual List/Custom
Wave 1/2/3/4/6/8/12/16
Bar Single/Dual/Triad
Vector Single/Dual
ZOOM1 and ZOOM2 (divided lower display area)
FFT1 and FFT2 (divided lower display area)
XY1 and XY2 (divided lower display area)
Numerical Display
Displaying functions: Please refer to Measurement function
Max digit of numeric display: Selected full 5 digits (displaying 99999), or 6 digits (999999).
Number of displayed items: Select from 4, 8, 16, Matrix, All, Single List, Dual List, and Custom
Waveform Display
Displaying items: Maximum 16 waveforms
Voltage, current and power of Element 1
Voltage, current and power of Element 2 (or AUX3 and AUX4 of Element 2)
Voltage, current and power of Element 3 (or AUX5 and AUX6 of Element 3)
Voltage, current and power of Element 4 (or AUX7 and AUX8 of Element 4)
MATH 1 to MATH 8
Vector Bar Graph Display (option)
Vector display: Display the phase angle between the fundamental voltage signal and fundamental current signal as a vector
Bar graph display: Display a bar graph of the amplitude of each harmonics when it is harmonic measurement
Zoom Display
Zoom: Expand the displayed waveform along with the time axis (up to 2 separate locations). The zoom position can be automatically scrolled.
FFT Display
FFT Power speculum of input waveform, Max. two windows
X-Y display
X-Y Display: The X and Y axes can be selected from Un/In/Pn/AUXn, MATHn (Max. four traces, two windows)
Measurement Function and Conditions
Crest Factor: Up to 200 (effective minimum input). Up to 2 (rated input) CfU: Voltage crest factor, CfI: Current crest factor
Measurement period: Measurement period to calculate numerical values
– Period of measurement update cycle based on zero crossing or external gate signal source signal
– 8192 points from specified by start cursor for harmonic measurement Wiring method 1P2W (Single phase 2 wire), 1P3W (Single phase 3 wire), 3P3W (3 phase 3
Wiring method: 1P2W (Single phase 2 wire), 1P3W (Single phase 3 wire), 3P3W (3 phase 3 wire), 3V3A (3 phase 3 wire, 3 power meter method), 3P4W (3 phase 4 wire)
Scaling: 0.0001 to 99999.9999 can be set for scaling of VT ratio, CT ratio and power ratio when external current sensor, VT or CT are used for the input. Linear scaling function is available for AUX module (760851)
Frequency measurement
Number of displayed digits: Full 5 digits (99999)
Max frequency: 5.0000 MHz
Accuracy: ±0.1 of reading
Frequency Measurement filter: Same as Zero-cross filter (OFF/100 Hz/500 Hz/2 kHz/20 kHz)
Harmonics measurement
Method: PLL synchronization method (not available for external sampling clock function)
Frequency range: The range for the fundamental frequency of the PLL source is 20 Hz to 6.4 kHz, and sampling frequency is more than 2 MS/s. Time/div is 2 ms/div or higher. ACQ Time Base is set to Int
FFT data length: 8192, the analysis (calculation) start point can be set freely in the acquisition memory data
Window function: Rectangular
Accuracy: Line filter OFF
Add below expression to normal measurement
Voltage & current: ( 0.001 × f + 0.001 × n ) % of reading + 0.1% of range
Power: (0.002 × f + 0.002 × n ) % of reading + 0.2% of range
Analysis Functions
Power value calculation: Calculate Voltage, Current. Power, Delta parameters, frequency and AUX values from captured waveforms
Apparent power, reactive power and power factor and those Sigma values are calculated from the Voltage, Current and Power values
Automated measurement of
Satistic processing:
Up to 24 items can be displayed P-P, Amp, Max, Min, High, Low, Avg, Mid, Rms, Sdev, +OvrShoot, -OvrShoot, Rise, Fall, Freq, Period, +Width, -Width, Duty, Pulse,Burst1, Burst2, AvgFreq, AvgPeriod, Int1TY, Int2TY, Int1XY, Int2XY, Int1hXY (IntegPower/IntegCurrent) Int2hXY (IntegPower/IntegCurrent)
Cyclic statistical processing: Application items: Automated measurement values of waveform parameters
Statistical items: Max, Min, Avg, Sdv, and Cnt
User defined computation
Max 8 expressions for waveforms MATH1 to MATH8, Max. 4 Mpoint, regarding Digital filter +, -, *, /, SHIFT, ABS, SQRT, LOG, EXP, NEG, SIN, COS, TAN, ATAN, PH, DIF, DDIF, INTG, IINTG, BIN, SQR, CUBE, F1, F2, FV, PWHH, PWHL, PWLH, PWLL, PWXX, DUTYH, DUTYL, FILT1, FILT2, HLBT, MEAN, LS-, PS-, PSD-, CS-, TF-, CH-, MAG, LOGMAG, PHASE, REAL, IMAG, TREND, TRENDM, TRENDD, TRENDF, -HH, -LL, -XX and ZC
User defined computation
Max. 20 expressions, F1 to F20
+, -, *, /, ABS, SQRT, LOG, EXP and NEG
Desckew function: Compensate the phase different between power voltage and current modules for power measurement element
Communication: GPIB, Ethernet, USB, IRIG, EXT I/O, SD card slot, TRIGGER IN, TRIGGER OUT, EXT CLK IN
Operating Temperature: Ambient Temperate: 23 +/- 5 degree, Ambient humidity: 20 to 80%RH, Supply Voltage and frequency Within +/- 1% of rating, Altitude: 2000 m or lessAfter the PX8000 has been warmed up for 30 minutes and then calibration has been performed.
Power supply: 100 to 120 VAC / 220 to 240 VAC (Auto switching)
Power consumption: Max 200 VA
Withstand voltage: 500 VAC for one minute between the power supply and case
nsulation resistance: 10 MOHM or more for 500 VDC between the power supply and case
Dimensions: 394 mm (W) x 259 mm (H) x 215 mm (D)
Weight: Approx. 6.5 kg (weight of the PX8000 only without paper and /M2, /B5, /C20, /G5 and /P4 options)