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Harmonic Power Measurement Certified to ISO 17025 or ANSI Z540

Jul 29, 2019

Wide-band Power Meter, Model WPM

The model WPM wide-band power meter measures and displays voltage, current, power, and energy parameters for single-phase or three-phase systems. Applications include measurement of PWM generated waveforms used in variable-frequency-drives (VFD's) and inverters. Units are also compliant with recent Department of Energy updates requiring 40th harmonic measurements (10 CFR Parts 429 and 431).


Local display is provided by three LED displays (no display is an option). Displayable parameters are grouped into four sets of three parameters, each selectable by front panel push-buttons. Remote display modules may be added as required to provide a display of up to eighteen different parameters.


Analog outputs may be provided by adding one or more D/A-4772 converters. Each of these converters provides up to eight output signals which may be assigned to any eight parameters.


Serial communications are provided through either an RS-232C, RS-422, RS-485 or USB interface, using a simple ASCII protocol. (USB is an external RS-232C-to-USB adapter.)


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Measure Watts/VARS/Watt(VAR)-Hours (5-500Hz)

Model Wxx

Measure simple to complex waveforms over a wide frequency range. The Wxx offers high accuracy, 5-500Hz frequency range, and analog or MODBUS communication outputs all within the Wxx's DIN-Rail package.


The Wxx line of transducers comes with many variations which allow you to choose the capability needed for your specific application.


You may select:

  • Watts, Watts and VARs, Watts/VARs and Watt-Hours/VAR-Hours
  • Over multiple Frequency Ranges
    • 50-60 Hz for simple loads
    • 5-500 Hz (excellent for VSI drives) and other, more-complex loads
    • Up to the 40th harmonic to ensure DoE Energy Star compliance
  • Voltage up to 400VL-N/ 693VL-L (with accuracy)
  • Accuracies from 0.5% of full scale to 0.2% of reading
  • Analog and pulse outputs


  • MODBUS communication


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To learn more about OSI capabilities
chat with us or call (614) 777-1005